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1.
Cell ; 175(2): 429-441.e16, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30245008

RESUMO

Targeting autophagy in cancer cells and in the tumor microenvironment are current goals of cancer therapy. However, components of canonical autophagy play roles in other biological processes, adding complexity to this goal. One such alternative function of autophagy proteins is LC3-associated phagocytosis (LAP), which functions in phagosome maturation and subsequent signaling events. Here, we show that impairment of LAP in the myeloid compartment, rather than canonical autophagy, induces control of tumor growth by tumor-associated macrophages (TAM) upon phagocytosis of dying tumor cells. Single-cell RNA sequencing (RNA-seq) analysis revealed that defects in LAP induce pro-inflammatory gene expression and trigger STING-mediated type I interferon responses in TAM. We found that the anti-tumor effects of LAP impairment require tumor-infiltrating T cells, dependent upon STING and the type I interferon response. Therefore, autophagy proteins in the myeloid cells of the tumor microenvironment contribute to immune suppression of T lymphocytes by effecting LAP.


Assuntos
Tolerância Imunológica/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Fagocitose/fisiologia , Animais , Autofagia/imunologia , Linhagem Celular , Interações Hospedeiro-Patógeno , Humanos , Tolerância Imunológica/imunologia , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Células Mieloides/metabolismo , Fagossomos/fisiologia , Linfócitos T/metabolismo , Microambiente Tumoral/fisiologia
2.
J Infect Dis ; 227(12): 1364-1375, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36763010

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection triggers activation of the NLRP3 inflammasome, which promotes inflammation and aggravates severe COVID-19. Here, we report that SARS-CoV-2 induces upregulation and activation of human caspase-4/CASP4 (mouse caspase-11/CASP11), and this process contributes to NLRP3 activation. In vivo infections performed in transgenic hACE2 humanized mice, deficient or sufficient for Casp11, indicate that hACE2 Casp11-/- mice were protected from disease development, with the increased pulmonary parenchymal area, reduced clinical score of the disease, and reduced mortality. Assessing human samples from fatal cases of COVID-19, we found that CASP4 was expressed in patient lungs and correlated with the expression of inflammasome components and inflammatory mediators, including CASP1, IL1B, IL18, and IL6. Collectively, our data establish that CASP4/11 promotes NLRP3 activation and disease pathology, revealing a possible target for therapeutic interventions for COVID-19.


Assuntos
COVID-19 , Inflamassomos , Camundongos , Animais , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Macrófagos/metabolismo , COVID-19/metabolismo , SARS-CoV-2/metabolismo , Camundongos Transgênicos
3.
J Infect Dis ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015657

RESUMO

BACKGROUND: The inflammation in the lungs and other vital organs in COVID-19 are characterized by the presence of neutrophils and high concentration of neutrophil extracellular traps (NETs), which also seems to mediate host tissue damage. However, it is not known whether NETs could have virucidal activity against SARS-CoV-2. METHODS: We investigated whether NETs could prevent SARS-CoV-2 replication in neutrophils and epithelial cells, and what the consequence of NETs degradation in K18-humanized ACE2 transgenic mice infected with SARS-CoV-2. RESULTS: Here, by immunofluorescence microscopy we observed that viral particles co-localize with NETs in neutrophils isolated from COVID-19 patients or from healthy individuals and infected in vitro. The inhibition of NETs production increased virus replication in neutrophils. In parallel, we observed that NETs inhibited virus abilities to infect and replicate in epithelial cells after 24 h of infection. Degradation of NETs with DNase I prevented their virucidal effect in vitro. Using K18-humanized ACE2 transgenic mice we observed a higher viral load in animals treated with DNase I. On the other hand, the virucidal effect of NETs was not dependent on neutrophil elastase or myeloperoxidase activity. CONCLUSION: Our results provide evidence of the role of NETosis as a mechanism of SARS-CoV-2 viral capture and inhibition.

5.
Crit Care ; 26(1): 206, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799268

RESUMO

BACKGROUND: The release of neutrophil extracellular traps (NETs) is associated with inflammation, coagulopathy, and organ damage found in severe cases of COVID-19. However, the molecular mechanisms underlying the release of NETs in COVID-19 remain unclear. OBJECTIVES: We aim to investigate the role of the Gasdermin-D (GSDMD) pathway on NETs release and the development of organ damage during COVID-19. METHODS: We performed a single-cell transcriptome analysis in public data of bronchoalveolar lavage. Then, we enrolled 63 hospitalized patients with moderate and severe COVID-19. We analyze in blood and lung tissue samples the expression of GSDMD, presence of NETs, and signaling pathways upstreaming. Furthermore, we analyzed the treatment with disulfiram in a mouse model of SARS-CoV-2 infection. RESULTS: We found that the SARS-CoV-2 virus directly activates the pore-forming protein GSDMD that triggers NET production and organ damage in COVID-19. Single-cell transcriptome analysis revealed that the expression of GSDMD and inflammasome-related genes were increased in COVID-19 patients. High expression of active GSDMD associated with NETs structures was found in the lung tissue of COVID-19 patients. Furthermore, we showed that activation of GSDMD in neutrophils requires active caspase1/4 and live SARS-CoV-2, which infects neutrophils. In a mouse model of SARS-CoV-2 infection, the treatment with disulfiram inhibited NETs release and reduced organ damage. CONCLUSION: These results demonstrated that GSDMD-dependent NETosis plays a critical role in COVID-19 immunopathology and suggests GSDMD as a novel potential target for improving the COVID-19 therapeutic strategy.


Assuntos
Tratamento Farmacológico da COVID-19 , Armadilhas Extracelulares , Animais , Dissulfiram/metabolismo , Armadilhas Extracelulares/metabolismo , Camundongos , Neutrófilos/metabolismo , SARS-CoV-2
6.
Nature ; 533(7601): 115-9, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27096368

RESUMO

Defects in clearance of dying cells have been proposed to underlie the pathogenesis of systemic lupus erythematosus (SLE). Mice lacking molecules associated with dying cell clearance develop SLE-like disease, and phagocytes from patients with SLE often display defective clearance and increased inflammatory cytokine production when exposed to dying cells in vitro. Previously, we and others described a form of noncanonical autophagy known as LC3-associated phagocytosis (LAP), in which phagosomes containing engulfed particles, including dying cells, recruit elements of the autophagy pathway to facilitate maturation of phagosomes and digestion of their contents. Genome-wide association studies have identified polymorphisms in the Atg5 (ref. 8) and possibly Atg7 (ref. 9) genes, involved in both canonical autophagy and LAP, as markers of a predisposition for SLE. Here we describe the consequences of defective LAP in vivo. Mice lacking any of several components of the LAP pathway show increased serum levels of inflammatory cytokines and autoantibodies, glomerular immune complex deposition, and evidence of kidney damage. When dying cells are injected into LAP-deficient mice, they are engulfed but not efficiently degraded and trigger acute elevation of pro-inflammatory cytokines but not anti-inflammatory interleukin (IL)-10. Repeated injection of dying cells into LAP-deficient, but not LAP-sufficient, mice accelerated the development of SLE-like disease, including increased serum levels of autoantibodies. By contrast, mice deficient in genes required for canonical autophagy but not LAP do not display defective dying cell clearance, inflammatory cytokine production, or SLE-like disease, and, like wild-type mice, produce IL-10 in response to dying cells. Therefore, defects in LAP, rather than canonical autophagy, can cause SLE-like phenomena, and may contribute to the pathogenesis of SLE.


Assuntos
Autofagia , Inflamação/patologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Animais , Complexo Antígeno-Anticorpo/metabolismo , Autoanticorpos/sangue , Autofagia/genética , Citocinas/biossíntese , Citocinas/sangue , Inflamação/sangue , Inflamação/genética , Interleucina-10/biossíntese , Rim/metabolismo , Rim/patologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/genética , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Fagócitos/citologia , Fagócitos/fisiologia , Fagossomos/fisiologia
7.
Environ Res ; 214(Pt 4): 114157, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36027956

RESUMO

In this study, we investigated factors that influence the differences in exposure of perfluoroalkyl acids (PFAAs) from eight species of Antarctic seabirds, including Pygoscelis penguins, Stercorarius maccormicki, and Macronectes giganteus. We analyzed the relationship between foraging ecology (based on δ13C, δ15N, and δ34S values) and PFAAs accumulated in eggs and breast feathers. Ten out of 15 targeted PFAAs were detected in eggs compared to eight in feathers. Mean ∑PFAA concentrations in feathers ranged from 0.47 in P. antarcticus to 17.4 ng/g dry weight (dw) in S. maccormicki. In eggs, ∑PFAA concentrations ranged from 3.51 in P. adeliae to 117 ng/g dw in S. maccormicki. The highest concentrations of most PFAAs were found in trans-equatorial migrators such as S. maccormicki, probably due their high trophic position and higher concentrations of PFAAs in the Northern Hemisphere compared to the Southern Hemisphere. Based on stable isotopes correlations, our results suggest that the trophic position (δ15N) and the foraging area (δ13C and δ34S) influence PFAAs concentrations in Antarctic seabirds. Our results point to the possibility that long-distance migratory birds may have as bio-vectors in the transport of pollutants, including PFCAs, in Antarctic environments, although this must be further confirmed in future studies using a mass balanced approach, such as extractable organofluorine (EOF).


Assuntos
Poluentes Ambientais , Fluorocarbonos , Spheniscidae , Animais , Regiões Antárticas , Monitoramento Ambiental/métodos , Plumas/química , Fluorocarbonos/análise
8.
PLoS Pathog ; 13(8): e1006502, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28771586

RESUMO

Legionella pneumophila is a Gram-negative, flagellated bacterium that survives in phagocytes and causes Legionnaires' disease. Upon infection of mammalian macrophages, cytosolic flagellin triggers the activation of Naip/NLRC4 inflammasome, which culminates in pyroptosis and restriction of bacterial replication. Although NLRC4 and caspase-1 participate in the same inflammasome, Nlrc4-/- mice and their macrophages are more permissive to L. pneumophila replication compared with Casp1/11-/-. This feature supports the existence of a pathway that is NLRC4-dependent and caspase-1/11-independent. Here, we demonstrate that caspase-8 is recruited to the Naip5/NLRC4/ASC inflammasome in response to flagellin-positive bacteria. Accordingly, caspase-8 is activated in Casp1/11-/- macrophages in a process dependent on flagellin, Naip5, NLRC4 and ASC. Silencing caspase-8 in Casp1/11-/- cells culminated in macrophages that were as susceptible as Nlrc4-/- for the restriction of L. pneumophila replication. Accordingly, macrophages and mice deficient in Asc/Casp1/11-/- were more susceptible than Casp1/11-/- and as susceptible as Nlrc4-/- for the restriction of infection. Mechanistically, we found that caspase-8 activation triggers gasdermin-D-independent pore formation and cell death. Interestingly, caspase-8 is recruited to the Naip5/NLRC4/ASC inflammasome in wild-type macrophages, but it is only activated when caspase-1 or gasdermin-D is inhibited. Our data suggest that caspase-8 activation in the Naip5/NLRC4/ASC inflammasome enable induction of cell death when caspase-1 or gasdermin-D is suppressed.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Caspase 1/imunologia , Caspase 8/imunologia , Inflamassomos/imunologia , Doença dos Legionários/imunologia , Animais , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Ligação ao Cálcio , Caspase 1/metabolismo , Caspase 8/metabolismo , Modelos Animais de Doenças , Ativação Enzimática/imunologia , Ensaio de Imunoadsorção Enzimática , Técnicas de Silenciamento de Genes , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Legionella pneumophila , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Inibidora de Apoptose Neuronal , Proteínas de Ligação a Fosfato , Reação em Cadeia da Polimerase em Tempo Real
9.
J Immunol ; 195(5): 2303-11, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26232428

RESUMO

Gram-negative bacteria from the Legionella genus are intracellular pathogens that cause a severe form of pneumonia called Legionnaires' disease. The bacteria replicate intracellularly in macrophages, and the restriction of bacterial replication by these cells is critical for host resistance. The activation of the NAIP5/NLRC4 inflammasome, which is readily triggered in response to bacterial flagellin, is essential for the restriction of bacterial replication in murine macrophages. Once activated, this inflammasome induces pore formation and pyroptosis and facilitates the restriction of bacterial replication in macrophages. Because investigations related to the NLRC4-mediated restriction of Legionella replication were performed using mice double deficient for caspase-1 and caspase-11, we assessed the participation of caspase-1 and caspase-11 in the functions of the NLRC4 inflammasome and the restriction of Legionella replication in macrophages and in vivo. By using several species of Legionella and mice singly deficient for caspase-1 or caspase-11, we demonstrated that caspase-1 but not caspase-11 was required for pore formation, pyroptosis, and restriction of Legionella replication in macrophages and in vivo. By generating F1 mice in a mixed 129 × C57BL/6 background deficient (129 × Casp-11(-/-) ) or sufficient (129 × C57BL/6) for caspase-11 expression, we found that caspase-11 was dispensable for the restriction of Legionella pneumophila replication in macrophages and in vivo. Thus, although caspase-11 participates in flagellin-independent noncanonical activation of the NLRP3 inflammasome, it is dispensable for the activities of the NLRC4 inflammasome. In contrast, functional caspase-1 is necessary and sufficient to trigger flagellin/NLRC4-mediated restriction of Legionella spp. infection in macrophages and in vivo.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Caspase 1/imunologia , Caspases/imunologia , Legionella/imunologia , Doença dos Legionários/imunologia , Macrófagos/imunologia , Piroptose/imunologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Western Blotting , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Caspases/genética , Caspases/metabolismo , Caspases Iniciadoras , Linhagem Celular , Células Cultivadas , Ativação Enzimática/imunologia , Flagelos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Interleucina-1beta/biossíntese , Interleucina-1beta/imunologia , Legionella/classificação , Legionella/fisiologia , Legionella pneumophila/imunologia , Legionella pneumophila/fisiologia , Doença dos Legionários/genética , Doença dos Legionários/microbiologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Piroptose/genética , Especificidade da Espécie
11.
Infect Immun ; 84(9): 2439-48, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27297388

RESUMO

Coxiella burnetii is a Gram-negative bacterium that causes Q fever in humans. Q fever is an atypical pneumonia transmitted through inhalation of contaminated aerosols. In mammalian lungs, C. burnetii infects and replicates in several cell types, including alveolar macrophages (AMs). The innate immunity and signaling pathways operating during infection are still poorly understood, in part because of the lack of relevant host cell models for infection in vitro In the study described here, we investigated and characterized the infection of primary murine AMs by C. burnetii phase II in vitro Our data reveal that AMs show a pronounced M2 polarization and are highly permissive to C. burnetii multiplication in vitro Murine AMs present an increased susceptibility to infection in comparison to primary bone marrow-derived macrophages. AMs support more than 2 logs of bacterial replication during 12 days of infection in culture, similar to highly susceptible host cells, such as Vero and THP-1 cells. As a proof of principle that AMs are useful for investigation of C. burnetii replication, we performed experiments with AMs from Nos2(-/-) or Ifng(-/-) mice. In the absence of gamma interferon and nitric oxide synthase 2 (NOS2), AMs were significantly more permissive than wild-type cells. In contrast, AMs from Il4(-/-) mice were more restrictive to C. burnetii replication, supporting the importance of M2 polarization for the permissiveness of AMs to C. burnetii replication. Collectively, our data account for understanding the high susceptibility of alveolar macrophages to bacterial replication and support the use of AMs as a relevant model of C. burnetii growth in primary macrophages.


Assuntos
Coxiella burnetii/imunologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/microbiologia , Alvéolos Pulmonares/imunologia , Alvéolos Pulmonares/microbiologia , Animais , Células Cultivadas , Imunidade Inata/imunologia , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/imunologia , Febre Q/imunologia , Febre Q/microbiologia , Transdução de Sinais/imunologia
12.
J Immunol ; 190(7): 3629-38, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23460746

RESUMO

Pathogens are detected by innate immune receptors that, upon activation, orchestrate an appropriate immune response. Recent studies revealed the intracellular signaling cascades involved in the TLR-initiated immune response to Brucella abortus infection. However, no report has elucidated the role of inflammasome receptors in Brucella recognition. Therefore, we decided to investigate the function of NLRC4, NLRP3, and AIM2 in sensing Brucella. In this study, we showed that NLRC4 is not required to induce caspase-1 activation and further secretion of IL-1ß by B. abortus in macrophages. In contrast, we determined that AIM2, which senses Brucella DNA, and NLRP3 are partially required for caspase-1 activation and IL-1ß secretion. Additionally, mitochondrial reactive oxygen species induced by Brucella were implicated in IL-1ß production. Furthermore, AIM2, NLRP3, ASC, and caspase-1 knockout mice were more susceptible to B. abortus infection than were wild-type animals, suggesting that multiple ASC-dependent inflammasomes contribute to host protection against infection. This protective effect is due to the inflammatory response caused by IL-1ß and IL-18 rather than pyroptosis, because we observed augmented bacterial burden in IL-1R and IL-18 knockout mice. Finally, we determined that bacterial type IV secretion system VirB and live, but not heat-killed, Brucella are required for full inflammasome activation in macrophages during infection. Taken together, our results indicate that Brucella is sensed by ASC inflammasomes that collectively orchestrate a robust caspase-1 activation and proinflammatory response.


Assuntos
Sistemas de Secreção Bacterianos , Brucella abortus/imunologia , Brucella abortus/metabolismo , Brucelose/imunologia , Brucelose/metabolismo , Caspase 1/metabolismo , Proteínas do Citoesqueleto/metabolismo , Inflamassomos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Caspase 1/genética , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA , Ativação Enzimática , Predisposição Genética para Doença , Granuloma/imunologia , Granuloma/metabolismo , Granuloma/microbiologia , Imunidade Inata , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Fígado/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo
13.
Micromachines (Basel) ; 15(2)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38398999

RESUMO

Isothermal amplification methods have become popular in research due to the simplicity of the technology needed to run the reactions. Specifically, loop-mediated isothermal amplification (LAMP) has been widely used for various applications since first reported in 2000. LAMP reactions are commonly monitored with the use of colorimetry. Although color changes associated with positive amplification are apparent to the naked eye, this detection method is subjective due to inherent differences in visual perception from person to person. The objectivity of the colorimetric detection method may be improved by programmed image capture over time with simultaneous heating. As such, the development of a novel, one-step, automated, and integrated analysis system capable of performing these tasks in parallel is detailed herein. The device is adaptable to multiple colorimetric dyes, cost-effective, 3D-printed for single-temperature convective heating, and features an easy-to-use LabVIEW software program developed for automated image analysis. The device was optimized and subsequently validated using four messenger-RNA targets and mock forensic samples. The performance of our device was determined to be comparable to that of a conventional thermal cycler and smartphone image analysis, respectively. Moreover, the outlined system is capable of objective colorimetric analysis, with exceptional throughput of up to 96 samples at once.

14.
Rev Soc Bras Med Trop ; 57: e008032024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537001

RESUMO

A 22-year-old female researcher was bitten by a Leptodeira annulata on the index finger of the left hand during a contention activity. After removing the snake, a little bleeding and redness was observed in the bite region, accompanied by fang marks. Thirty minutes later, edema had progressed to the dorsum of the hand. After four hours, edema persisted, but the bitten area was slightly whitened. Treatment consisted of antibiotics and anti-inflammatory drugs. The edema resolved completely and disappeared after 48 hours. Overall, this report presents the first case of envenomation in humans caused by Leptodeira annulata in Brazil.


Assuntos
Colubridae , Lagartos , Mordeduras de Serpentes , Humanos , Animais , Feminino , Adulto Jovem , Adulto , Mordeduras de Serpentes/complicações , Brasil , Edema/etiologia , Antivenenos/uso terapêutico
15.
Arthritis Rheum ; 64(2): 474-84, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21952942

RESUMO

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 B(4) (LTB(4) ) 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-1ß (IL-1ß), 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, LTB(4) activity, cytokine (IL-1ß, 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 neutrophil-dependent hypernociception. MSU crystal-induced neutrophil influx was CXCR2-dependent and relied on the induction of CXCL1 in an NLRP3/ASC/caspase 1/IL-1ß/MyD88-dependent manner. LTB(4) was produced rapidly after injection of MSU crystals, and this was necessary for caspase 1-dependent IL-1ß production and consequent release of CXCR2-acting chemokines in vivo. In vitro, macrophages produced LTB(4) after MSU crystal injection, and LTB(4) was relevant in the MSU crystal-induced maturation of IL-1ß. Mechanistically, LTB(4) drove MSU crystal-induced production of ROS and ROS-dependent activation of the NLRP3 inflammasome. CONCLUSION: These results reveal the role of the NLRP3 inflammasome in mediating MSU crystal-induced inflammation and dysfunction of the joints, and highlight a previously unrecognized role of LTB(4) in driving NLRP3 inflammasome activation in response to MSU crystals, both in vitro and in vivo.


Assuntos
Proteínas de Transporte/metabolismo , Gota/metabolismo , Hiperalgesia/metabolismo , Inflamassomos/metabolismo , Leucotrieno B4/metabolismo , Infiltração de Neutrófilos/fisiologia , Neutrófilos/metabolismo , Animais , Caspase 1/metabolismo , Citocinas/metabolismo , Gota/induzido quimicamente , Gota/imunologia , Hiperalgesia/imunologia , Inflamassomos/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Leucotrieno B4/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neutrófilos/imunologia , Espécies Reativas de Oxigênio/metabolismo , Membrana Sinovial/imunologia , Membrana Sinovial/metabolismo , Ácido Úrico/farmacologia
16.
J Affect Disord ; 326: 73-82, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36709828

RESUMO

BACKGROUND: Major depressive disorder is the most common type of mental disorder. The biological pathway by which exercise promotes its antidepressant effects remains uncleared. This study aimed to systematically review the chronic effect of exercise on blood biomarkers and its association with changes in depressive symptoms in adults with major depressive disorder. METHODS: Randomized controlled trials (RCT) published until February 2020 were screened in seven databases. Studies were systematically reviewed by two independent reviewers. Random effect meta-analysis was performed and reported as standardized mean differences (SMD) and 95 % confidence interval (CI). The meta- analysis protocol was registered with PROSPERO (CRD42021221177). RESULTS: From 3865 records, 12 studies (N = 757 participants, mean age [SD]: 43.0 [11.0], 66.2 % women) were included in this review. Exercise training resulted in superior increase in circulating BDNF (SMD: 0.44, 95%CI: 0.15, 0.73) and kynurenine (SMD: 0.29, 95%CI: 0.04, 0.54), and decrease depressive symptoms (SMD: -0.72, 95%CI: -1.08, -0.37) in adults with major depression disorder compared to control groups. Multivariate meta-regression analysis showed that improvements in circulating levels of BDNF, kynurenine and interleukyn-6 were associated with decreases in depressive symptoms. LIMITATIONS: Results were not stratified by the type of medication used by participants due to the lack of reporting of the included studies. Few studies provided data on other biomarkers (e.g., TNF-α and IL-10) besides BNDF and kynurenine. CONCLUSIONS: Antidepressant effect of exercise may be triggered by improved circulating levels of BNDF, kynurenine, and interleukine-6 in adults with major depressive disorder.


Assuntos
Depressão , Transtorno Depressivo Maior , Adulto , Feminino , Humanos , Masculino , Depressão/tratamento farmacológico , Fator Neurotrófico Derivado do Encéfalo , Cinurenina , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Exercício Físico , Neurotransmissores
17.
Bio Protoc ; 13(24): e4903, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38156029

RESUMO

Clearance of dying cells, named efferocytosis, is a pivotal function of professional phagocytes that impedes the accumulation of cell debris. Efferocytosis can be experimentally assessed by differentially tagging the target cells and professional phagocytes and analyzing by cell imaging or flow cytometry. Here, we describe an assay to evaluate the uptake of apoptotic cells (ACs) by human macrophages in vitro by labeling the different cells with commercially available dyes and analysis by flow cytometry. We detail the methods to prepare and label human macrophages and apoptotic lymphocytes and the in vitro approach to determine AC uptake. This protocol is based on previously published literature and allows for in vitro modeling of the efficiency of AC engulfment during continual efferocytosis process. Also, it can be modified to evaluate the clearance of different cell types by diverse professional phagocytes.

18.
Anal Chim Acta ; 1249: 340826, 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-36868762

RESUMO

Biological evidence originating from victims of sexual assault is often comprised of unbalanced cellular mixtures with significantly higher contributions from the victim's genetic material. Enrichment of the forensically-critical sperm fraction (SF) with single-source male DNA relies on differential extraction (DE), a manually-intensive process that is prone to contamination. Due to DNA losses from sequential washing steps, some existing DE methods often fail to generate sufficient sperm cell DNA recovery for perpetrator(s) identification. Here, we propose an enzymatic, 'swab-in' rotationally-driven microfluidic device to achieve complete, self-contained, on-disc automation of the forensic DE workflow. This 'swab-in' approach retains the sample within the microdevice, enabling lysis of sperm cells directly from the evidence cutting to improve sperm cell DNA yield. We demonstrate clear proof-of-concept of a centrifugal platform that provides for timed reagent release, temperature control for sequential enzymatic reactions, and enclosed fluidic fractionation that allows for objective evaluation of the DE process chain with a total processing time of ≤15 min. On-disc extraction of buccal or sperm swabs establishes compatibility of the prototype disc with: 1) an entirely enzymatic extraction method, and 2) distinct downstream analysis modalities, such as the PicoGreen® DNA assay for nucleic acid detection and the polymerase chain reaction (PCR).


Assuntos
Microfluídica , Sêmen , Masculino , Humanos , Espermatozoides , Automação , Bioensaio
19.
Sci Rep ; 13(1): 13599, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37604833

RESUMO

The TIGIT+FOXP3+Treg subset (TIGIT+Tregs) exerts robust suppressive activity on cellular immunity and predisposes septic individuals to opportunistic infection. We hypothesized that TIGIT+Tregs could play an important role in intensifying the COVID-19 severity and hampering the defense against nosocomial infections during hospitalization. Herein we aimed to verify the association between the levels of the TIGIT+Tregs with the mechanical ventilation requirement, fatal outcome, and bacteremia during hospitalization. TIGIT+Tregs were immunophenotyped by flow cytometry from the peripheral blood of 72 unvaccinated hospitalized COVID-19 patients at admission from May 29th to August 6th, 2020. The patients were stratified during hospitalization according to their mechanical ventilation requirement and fatal outcome. COVID-19 resulted in a high prevalence of the TIGIT+Tregs at admission, which progressively increased in patients with mechanical ventilation needs and fatal outcomes. The prevalence of TIGIT+Tregs positively correlated with poor pulmonary function and higher plasma levels of LDH, HMGB1, FGL2, and TNF. The non-survivors presented higher plasma levels of IL-33, HMGB1, FGL2, IL-10, IL-6, and 5.54 times more bacteremia than survivors. Conclusions: The expansion of the TIGIT+Tregs in COVID-19 patients was associated with inflammation, lung dysfunction, bacteremia, and fatal outcome.


Assuntos
Bacteriemia , COVID-19 , Infecção Hospitalar , Proteína HMGB1 , Humanos , Respiração Artificial , Linfócitos T Reguladores , Receptores Imunológicos , Fibrinogênio
20.
iScience ; 26(12): 108366, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38047070

RESUMO

Airway epithelial cells (AEC) infected with SARS-CoV-2 may drive the dysfunction of macrophages during COVID-19. We hypothesized that the direct interaction of AEC with macrophages mediated by CD95/CD95L or indirect interaction mediated by IL-6 signaling are key steps for the COVID-19 severe acute inflammation. The interaction of macrophages with apoptotic and infected AEC increased CD95 and CD163 expression, and induced macrophage death. Macrophages exposed to tracheal aspirate with high IL-6 levels from intubated patients with COVID-19 or to recombinant human IL-6 exhibited decreased HLA-DR expression, increased CD95 and CD163 expression and IL-1ß production. IL-6 effects on macrophages were prevented by both CD95/CD95L antagonist and by IL-6 receptor antagonist and IL-6 or CD95 deficient mice showed significant reduction of acute pulmonary inflammation post-infection. Our findings show a non-canonical CD95L-CD95 pathway that simultaneously drives both macrophage activation and dysfunction and point to CD95/CD95L axis as therapeutic target.

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