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1.
Inflammation ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329636

RESUMO

Neutrophilic asthma is generally defined by poorly controlled symptoms and high levels of neutrophils in the lungs. Short-chain fatty acids (SCFAs) are proposed as nonpharmacological therapy for allergic asthma, but their impact on the neutrophilic asthma lacks evidence. SCFAs regulate immune cell responses and impact the inflammasome NLRP3, a potential pharmacological target for neutrophilic asthma. Here, we explored the capacity of SCFAs to mitigate murine-induced neutrophilic asthma and the contribution of NLRP3 to this asthma. The objective of this study is to analyze whether SCFAs can attenuate lung inflammation and tissue remodeling in murine neutrophilic asthma and NLRP3 contribution to this endotype. Wild-type (WT) C57BL6 mice orotracheally received 10 µg of HDM (house dust mite) in 80 µL of saline on days 0, 6-10. To explore SCFAs, each HDM group received 200 mM acetate, propionate, or butyrate. To explore NLRP3, Nlrp3 KO mice received the same protocol of HDM. On the 14th day, after euthanasia, bronchoalveolar lavage fluid (BALF) and lungs were collected to evaluate cellularity, inflammatory cytokines, and tissue remodeling. HDM group had increased BALF neutrophil influx, TNF-α, IFN-γ, IL-17A, collagen deposition, and mucus secretion compared to control. SCFAs distinctively attenuate lung inflammation. Only features of tissue remodeling were Nlrp3-dependent such as collagen deposition, mucus secretion, active TGF-ß cytokine, and IMs CD206+. SCFAs greatly decreased inflammatory cytokines and tissue remodeling. Only tissue remodeling was dependent on NLRP3. It reveals the potential of SCFAs to act as an additional therapy to mitigate neutrophilic asthma and the NLRP3 contribution to asthma.

2.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38139812

RESUMO

Anaplastic thyroid cancer (ATC) is an aggressive form of thyroid cancer (TC), accounting for 50% of total TC-related deaths. Although therapeutic approaches against TC have improved in recent years, the survival rate remains low, and severe adverse effects are commonly reported. However, unexplored alternatives based on natural compounds, such as lysicamine, an alkaloid found in plants with established cytotoxicity against breast and liver cancers, offer promise. Therefore, this study aimed to explore the antineoplastic effects of lysicamine in papillary TC (BCPAP) and ATC (HTH83 and KTC-2) cells. Lysicamine treatment reduced cell viability, motility, colony formation, and AKT activation while increasing the percentage of necrotic cells. The absence of caspase activity confirmed apoptosis-independent cell death. Necrostatin-1 (NEC-1)-mediated necrosome inhibition reduced lysicamine-induced necrosis in KTC-2, suggesting necroptosis induction via a reactive oxygen species (ROS)-independent mechanism. Additionally, in silico analysis predicted lysicamine target proteins, particularly those related to MAPK and TGF-ß signaling. Our study demonstrated lysicamine's potential as an antineoplastic compound in ATC cells with a proposed mechanism related to inhibiting AKT activation and inducing cell death.

3.
Front Immunol ; 14: 1282856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38124741

RESUMO

Inflammasomes are large protein complexes that, once activated, initiate inflammatory responses by activating the caspase-1 protease. They play pivotal roles in host defense against pathogens. The well-established role of NAIP/NLRC4 inflammasome in bacterial infections involves NAIP proteins functioning as sensors for their ligands. However, recent reports have indicated the involvement of NLRC4 in non-bacterial infections and sterile inflammation, even though the role of NAIP proteins and the exact molecular mechanisms underlying inflammasome activation in these contexts remain to be elucidated. In this study, we investigated the activation of the NAIP/NLRC4 inflammasome in response to Trypanosoma cruzi, the protozoan parasite responsible for causing Chagas disease. This parasite has been previously demonstrated to activate NLRP3 inflammasomes. Here we found that NAIP and NLRC4 proteins are also required for IL-1ß and Nitric Oxide (NO) release in response to T. cruzi infection, with their absence rendering macrophages permissive to parasite replication. Moreover, Nlrc4 -/- and Nlrp3 -/- macrophages presented similar impaired responses to T. cruzi, underscoring the non-redundant roles played by these inflammasomes during infection. Notably, it was the live trypomastigotes rather than soluble antigens or extracellular vesicles (EVs) secreted by them, that activated inflammasomes in a cathepsins-dependent manner. The inhibition of cathepsins effectively abrogated caspase-1 cleavage, IL-1ß and NO release, mirroring the phenotype observed in Nlrc4 -/-/Nlrp3 -/- double knockout macrophages. Collectively, our findings shed light on the pivotal role of the NAIP/NLRC4 inflammasome in macrophage responses to T. cruzi infection, providing new insights into its broader functions that extend beyond bacterial infections.


Assuntos
Infecções Bacterianas , Doença de Chagas , Trypanosoma cruzi , 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 , Trypanosoma cruzi/metabolismo , Caspase 1/metabolismo , Catepsinas/metabolismo , Macrófagos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteína Inibidora de Apoptose Neuronal/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-37368949

RESUMO

INTRODUCTION: There has been growing concern about the long-term effects of COVID-19 on mental health. The biological factors common to psychiatric conditions and COVID-19 are not yet fully understood. METHODOLOGY: We narratively reviewed prospective longitudinal studies that measured metabolic or inflammatory markers and assessed psychiatric sequalae and cognitive impairment in individuals with COVID-19 at least 3 months after the infection. A literature search identified three relevant cohort studies. RESULTS: Overall, depressive symptomatology and cognitive deficits persisted for up to one year after COVID-19; depression and cognitive changes were predicted by acute inflammatory markers, and changes in these markers correlated with changes in depressive symptomatology; female sex, obesity, and the presence of inflammatory markers were associated with more severe clusters of physical and mental health status in patients' self-perceived recovery; and plasma metabolic profiles of patients continued to differ from those of healthy controls three months after hospital discharge, which were associated with widespread alterations in neuroimaging, reflecting issues with white matter integrity. This is a non-systematic review and cautions should be made while interpreting the conclusions. CONCLUSION: In individuals affected by the COVID-19, prolonged exposure to stress and alterations in metabolic and inflammatory markers plays a central role in psychiatric sequalae and cognitive deficits in the long term.

5.
Cell Death Dis ; 13(12): 1029, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36481780

RESUMO

The NAIP/NLRC4 inflammasome is classically associated with the detection of bacterial invasion to the cytosol. However, recent studies have demonstrated that NAIP/NLRC4 is also activated in non-bacterial infections, and in sterile inflammation. Moreover, in addition to the well-established model for the detection of bacterial proteins by NAIP proteins, the participation of other cytosolic pathways in the regulation of NAIP/NLRC4-mediated responses has been reported in distinct contexts. Using pharmacological inhibition and genetic deletion, we demonstrate here that cathepsins, well known for their involvement in NLRP3 activation, also regulate NAIP/NLRC4 responses to cytosolic flagellin in murine and human macrophages. In contrast to that observed for NLRP3 agonists, cathepsins inhibition did not reduce ASC speck formation or caspase-1 maturation in response to flagellin, ruling out their participation in the effector phase of NAIP/NLRC4 activation. Moreover, cathepsins had no impact on NF-κB-mediated priming of pro-IL-1ß, thus suggesting these proteases act downstream of the NAIP/NLRC4 inflammasome activation. IL-1ß levels secreted in response to flagellin were reduced in the absence of either cathepsins or Gasdermin-D (GSDMD), a molecule involved in the induction of pyroptosis and cytokines release. Notably, IL-1ß secretion was abrogated in the absence of both GSDMD and cathepsins, demonstrating their non-redundant roles for the optimal IL-1ß release in response to cytosolic flagellin. Given the central role of NAIP/NLRC4 inflammasomes in controlling infection and, also, induction of inflammatory pathologies, many efforts have been made to uncover novel molecules involved in their regulation. Thus, our findings bring together a relevant contribution by describing the role of cathepsins as players in the NAIP/NLRC4-mediated responses.


Assuntos
Proteínas Adaptadoras de Sinalização CARD , Proteínas de Ligação ao Cálcio , Catepsinas , Gasderminas , Lisossomos , Proteína Inibidora de Apoptose Neuronal , Animais , Humanos , Camundongos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Catepsinas/metabolismo , Deleção de Genes , Proteína Inibidora de Apoptose Neuronal/metabolismo , Gasderminas/metabolismo , Interleucina-1beta/metabolismo
6.
Antimicrob Agents Chemother ; 66(11): e0028422, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36314800

RESUMO

Drug combinations and drug repurposing have emerged as promising strategies to develop novel treatments for infectious diseases, including Chagas disease. In this study, we aimed to investigate whether the repurposed drugs chloroquine (CQ) and colchicine (COL), known to inhibit Trypanosoma cruzi infection in host cells, could boost the anti-T. cruzi effect of the trypanocidal drug benznidazole (BZN), increasing its therapeutic efficacy while reducing the dose needed to eradicate the parasite. The combination of BZN and COL exhibited cytotoxicity to infected cells and low antiparasitic activity. Conversely, a combination of BZN and CQ significantly reduced T. cruzi infection in vitro, with no apparent cytotoxicity. This effect seemed to be consistent across different cell lines and against both the partially BZN-resistant Y and the highly BZN-resistant Colombiana strains. In vivo experiments in an acute murine model showed that the BZN+CQ combination was eight times more effective in reducing T. cruzi infection in the acute phase than BZN monotherapy. In summary, our results demonstrate that the concomitant administration of CQ and BZN potentiates the trypanocidal activity of BZN, leading to a reduction in the dose needed to achieve an effective response. In a translational context, it could represent a higher efficacy of treatment while also mitigating the adverse effects of high doses of BZN. Our study also reinforces the relevance of drug combination and repurposing approaches in the field of Chagas disease drug discovery.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Camundongos , Animais , Reposicionamento de Medicamentos , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
8.
Cell Death Dis ; 12(7): 692, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34247195

RESUMO

Chagas disease is a life-threatening disorder caused by the protozoan parasite Trypanosoma cruzi. Parasite-specific antibodies, CD8+ T cells, as well as IFN-γ and nitric oxide (NO) are key elements of the adaptive and innate immunity against the extracellular and intracellular forms of the parasite. Bim is a potent pro-apoptotic member of the Bcl-2 family implicated in different aspects of the immune regulation, such as negative selection of self-reactive thymocytes and elimination of antigen-specific T cells at the end of an immune response. Interestingly, the role of Bim during infections remains largely unidentified. To explore the role of Bim in Chagas disease, we infected WT, Bim+/-, Bim-/- mice with trypomastigotes forms of the Y strain of T. cruzi. Strikingly, our data revealed that Bim-/- mice exhibit a delay in the development of parasitemia followed by a deficiency in the control of parasite load in the bloodstream and a decreased survival compared to WT and Bim+/- mice. At the peak of parasitemia, peritoneal macrophages of Bim-/- mice exhibit decreased NO production, which correlated with a decrease in the pro-inflammatory Small Peritoneal Macrophage (SPM) subset. A similar reduction in NO secretion, as well as in the pro-inflammatory cytokines IFN-γ and IL-6, was also observed in Bim-/- splenocytes. Moreover, an impaired anti-T. cruzi CD8+ T-cell response was found in Bim-/- mice at this time point. Taken together, our results suggest that these alterations may contribute to the establishment of a delayed yet enlarged parasitic load observed at day 9 after infection of Bim-/- mice and place Bim as an important protein in the control of T. cruzi infections.


Assuntos
Proteína 11 Semelhante a Bcl-2/deficiência , Doença de Chagas/parasitologia , Trypanosoma cruzi/patogenicidade , Animais , Proteína 11 Semelhante a Bcl-2/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/parasitologia , Células Cultivadas , Doença de Chagas/genética , Doença de Chagas/imunologia , Doença de Chagas/metabolismo , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Parasita , Interferon gama/metabolismo , Interleucina-6/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Carga Parasitária , Baço/imunologia , Baço/metabolismo , Baço/parasitologia , Fatores de Tempo , Trypanosoma cruzi/imunologia
9.
Front Cell Infect Microbiol ; 11: 676183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123875

RESUMO

Deficiency in memory formation and increased immunosenescence are pivotal features of Trypanosoma cruzi infection proposed to play a role in parasite persistence and disease development. The vaccination protocol that consists in a prime with plasmid DNA followed by the boost with a deficient recombinant human adenovirus type 5, both carrying the ASP2 gene of T. cruzi, is a powerful strategy to elicit effector memory CD8+ T-cells against this parasite. In virus infections, the inhibition of mTOR, a kinase involved in several biological processes, improves the response of memory CD8+ T-cells. Therefore, our aim was to assess the role of rapamycin, the pharmacological inhibitor of mTOR, in CD8+ T response against T. cruzi induced by heterologous prime-boost vaccine. For this purpose, C57BL/6 or A/Sn mice were immunized and daily treated with rapamycin for 34 days. CD8+ T-cells response was evaluated by immunophenotyping, intracellular staining, ELISpot assay and in vivo cytotoxicity. In comparison with vehicle-injection, rapamycin administration during immunization enhanced the frequency of ASP2-specific CD8+ T-cells and the percentage of the polyfunctional population, which degranulated (CD107a+) and secreted both interferon gamma (IFNγ) and tumor necrosis factor (TNF). The beneficial effects were long-lasting and could be detected 95 days after priming. Moreover, the effects were detected in mice immunized with ten-fold lower doses of plasmid/adenovirus. Additionally, the highly susceptible to T. cruzi infection A/Sn mice, when immunized with low vaccine doses, treated with rapamycin, and challenged with trypomastigote forms of the Y strain showed a survival rate of 100%, compared with 42% in vehicle-injected group. Trying to shed light on the biological mechanisms involved in these beneficial effects on CD8+ T-cells by mTOR inhibition after immunization, we showed that in vivo proliferation was higher after rapamycin treatment compared with vehicle-injected group. Taken together, our data provide a new approach to vaccine development against intracellular parasites, placing the mTOR inhibitor rapamycin as an adjuvant to improve effective CD8+ T-cell response.


Assuntos
Vacinas Protozoárias , Trypanosoma cruzi , Animais , Linfócitos T CD8-Positivos , Camundongos , Camundongos Endogâmicos C57BL , Sirolimo/farmacologia , Vacinação
11.
Clin Sci (Lond) ; 135(5): 687-701, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33620070

RESUMO

Muscle tissue damage is one of the local effects described in bothropic envenomations. Bothropstoxin-I (BthTX-I), from Bothrops jararacussu venom, is a K49-phospholipase A2 (PLA2) that induces a massive muscle tissue injury, and, consequently, local inflammatory reaction. The NLRP3 inflammasome is a sensor that triggers inflammation by activating caspase 1 and releasing interleukin (IL)-1ß and/or inducing pyroptotic cell death in response to tissue damage. We, therefore, aimed to address activation of NLRP3 inflammasome by BthTX-I-associated injury and the mechanism involved in this process. Intramuscular injection of BthTX-I results in infiltration of neutrophils and macrophages in gastrocnemius muscle, which is reduced in NLRP3- and Caspase-1-deficient mice. The in vitro IL-1ß production induced by BthTX-I in peritoneal macrophages (PMs) requires caspase 1/11, ASC and NLRP3 and is dependent on adenosine 5'-triphosphate (ATP)-induced K+ efflux and P2X7 receptor (P2X7R). BthTX-I induces a dramatic release of ATP from C2C12 myotubes, therefore representing the major mechanism for P2X7R-dependent inflammasome activation in macrophages. A similar result was obtained when human monocyte-derived macrophages (HMDMs) were treated with BthTX-I. These findings demonstrated the inflammatory effect of BthTX-I on muscle tissue, pointing out a role for the ATP released by damaged cells for the NLRP3 activation on macrophages, contributing to the understanding of the microenvironment of the tissue damage of the Bothrops envenomation.


Assuntos
Venenos de Crotalídeos/toxicidade , Inflamassomos/metabolismo , Inflamação/induzido quimicamente , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Trifosfato de Adenosina , Animais , Bothrops , Caspase 1/deficiência , Linhagem Celular , Humanos , Macrófagos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/patologia , Doenças Musculares/induzido quimicamente , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Receptores Purinérgicos P2X7
12.
Cells ; 10(1)2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440601

RESUMO

This study evaluated the role of endogenous and exogenous annexin A1 (AnxA1) in the activation of the NLRP3 inflammasome in isolated peritoneal neutrophils. C57BL/6 wild-type (WT) and AnxA1 knockout mice (AnxA1-/-) received 0.3% carrageenan intraperitoneally and, after 3 h, the peritoneal exudate was collected. WT and AnxA1-/- neutrophils were then stimulated with lipopolysaccharide, followed by the NLRP3 agonists nigericin or ATP. To determine the exogenous effect of AnxA1, the neutrophils were pretreated with the AnxA1-derived peptide Ac2-26 followed by the NLRP3 agonists. Ac2-26 administration reduced NLRP3-derived IL-1ß production by WT neutrophils after nigericin and ATP stimulation. However, IL-1ß release was impaired in AnxA1-/- neutrophils stimulated by both agonists, and there was no further impairment in IL-1ß release with Ac2-26 treatment before stimulation. Despite this, ATP- and nigericin-stimulated AnxA1-/- neutrophils had increased levels of cleaved caspase-1. The lipidomics of supernatants from nigericin-stimulated WT and AnxA1-/- neutrophils showed potential lipid biomarkers of cell stress and activation, including specific sphingolipids and glycerophospholipids. AnxA1 peptidomimetic treatment also increased the concentration of phosphatidylserines and oxidized phosphocholines, which are lipid biomarkers related to the inflammatory resolution pathway. Together, our results indicate that exogenous AnxA1 negatively regulates NLRP3-derived IL-1ß production by neutrophils, while endogenous AnxA1 is required for the activation of the NLRP3 machinery.


Assuntos
Anexina A1/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neutrófilos/metabolismo , Animais , Inflamassomos/ultraestrutura , Interleucina-1beta/metabolismo , Lipídeos/química , Masculino , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo , Neutrófilos/ultraestrutura
13.
Curr Res Immunol ; 2: 175-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35492395

RESUMO

The content of tumor-derived extracellular vesicles (EVs) can regulate the tumor microenvironment and functionally acts in favor of cancer aggressiveness. To better elucidate the role of EVs in the interplay between immune system and tumor microenvironment, the purpose of this study was to analyze the effect of head and neck squamous cells carcinoma (HNSCC)-derived EVs on the modulation of inflammasomes - mediators of pyroptosis and secretion of inflammatory factors by macrophages. Our results showed that macrophages treated with the Vesicular Secretome Fraction (VSF) isolated from patient-derived HNSCC presented a reduction in the secretion of mature IL-1ß and caspase-1 without affecting cell viability. An analysis of the protein content of HNSCC-derived VSF by antibody array revealed that some of the most expressed proteins share a correlation with Transforming Growth Factor-beta (TGF-ß) activity. Since TGF-ß is related to the inhibition of the NF-kB-related pathways, including those required for the priming phase of the inflammasomes, we sought to evalute the interference of the VSF in the induction of inflammasome components. In fact, HNSCC-derived VSF inhibited the induction of pro-IL-1ß and pro-caspase-1 proteins and NLRP3 gene expression during the priming phase of inflammasome activation. Thus, our findings contribute to a better understanding of how tumor-derived EVs modulate inflammatory response by demonstrating their role in inhibiting NLRP3 inflammasomes.

14.
Clin Sci (Lond), v. 135, n. 5, p. 687-701, fev. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3584

RESUMO

Muscle tissue damage is one of the local effects described in bothropic envenomations. Bothropstoxin-I (BthTX-I), from B. jararacussu venom, is a K49-phospholipase A2 that induces a massive muscle tissue injury, and, consequently, local inflammatory reaction. The NLRP3 inflammasome is a sensor that triggers inflammation by activating caspase 1 and releasing IL-1b and/or inducing pyroptotic cell death in response to tissue damage. We, therefore, aimed to address activation of NLRP3 inflammasome by BthTX-I-associated injury and the mechanism involved in this process. Intramuscular injection of BthTX-I results in infiltration of neutrophils and macrophages in gastrocnemius muscle, which is reduced in NLRP3- and Caspase-1-deficient mice. The in vitro IL-1β production induced by BthTX-I- inperitoneal macrophages requires caspase 1/11, ASC and NLRP3 and is dependent of ATP-induced K+ efflux and P2X7R. BthTX-I induces a dramatic release of ATP from C2C12 myotubes, therefore representing the major mechanism for P2X7R-dependent inflammasome activation in macrophages. A similar result was obtained when human monocyte-derived macrophages were treated with BthTX-I. These findings demonstrated the inflammatory effect of BthTX-I on muscle tissue, pointing out a role for the ATP released by damaged cells for the NLRP3 activation on macrophages, contributing to the understanding of the microenvironment of the tissue damage of the Bothrops envenomation.

15.
Nat Rev Immunol ; 20(10): 594-602, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913283

RESUMO

The COVID-19 pandemic is shining a spotlight on the field of immunology like never before. To appreciate the diverse ways in which immunologists have contributed, Nature Reviews Immunology invited the president of the International Union of Immunological Societies and the presidents of 15 other national immunology societies to discuss how they and their members responded following the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).


Assuntos
COVID-19/epidemiologia , Infecções por Coronavirus/epidemiologia , Cooperação Internacional , Pandemias , Pneumonia Viral/epidemiologia , Síndrome Respiratória Aguda Grave/epidemiologia , Sociedades Científicas/organização & administração , Antivirais/síntese química , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/terapia , Vacinas contra COVID-19 , Relações Comunidade-Instituição , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Saúde Global/tendências , Humanos , Educação de Pacientes como Assunto/organização & administração , Equipamento de Proteção Individual/provisão & distribuição , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/terapia , Vacinas Virais/biossíntese
16.
PLoS Negl Trop Dis ; 14(6): e0008414, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32574175

RESUMO

Chemokine receptor type 3 (CXCR3) plays an important role in CD8+ T cells migration during intracellular infections, such as Trypanosoma cruzi. In addition to chemotaxis, CXCR3 receptor has been described as important to the interaction between antigen-presenting cells and effector cells. We hypothesized that CXCR3 is fundamental to T. cruzi-specific CD8+ T cell activation, migration and effector function. Anti-CXCR3 neutralizing antibody administration to acutely T. cruzi-infected mice decreased the number of specific CD8+ T cells in the spleen, and those cells had impaired in activation and cytokine production but unaltered proliferative response. In addition, anti-CXCR3-treated mice showed decreased frequency of CD8+ T cells in the heart and numbers of plasmacytoid dendritic cells in spleen and lymph node. As CD8+ T cells interacted with plasmacytoid dendritic cells during infection by T. cruzi, we suggest that anti-CXCR3 treatment lowers the quantity of plasmacytoid dendritic cells, which may contribute to impair the prime of CD8+ T cells. Understanding which molecules and mechanisms guide CD8+ T cell activation and migration might be a key to vaccine development against Chagas disease as those cells play an important role in T. cruzi infection control.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Doença de Chagas/imunologia , Quimiocinas/metabolismo , Células Dendríticas/imunologia , Ativação Linfocitária/imunologia , Receptores CXCR3/metabolismo , Trypanosoma cruzi/imunologia , Animais , Movimento Celular , Doença de Chagas/parasitologia , Citoplasma/metabolismo , Citoplasma/parasitologia , Modelos Animais de Doenças , Feminino , Coração , Controle de Infecções , Camundongos , Camundongos Endogâmicos C57BL , Baço/imunologia
17.
Immunity ; 52(6): 890-892, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32553174

RESUMO

Caspase-8 is a master regulator of cell death pathways, although its regulation during inflammation remains elusive. Using elegant mouse genetic approaches, Schwarzer et al. and Tummers et al. revealed the importance of FADD in regulating caspase-8-mediated inflammatory responses and gut homeostasis.


Assuntos
Microbioma Gastrointestinal , Animais , Apoptose , Caspase 8/genética , Caspase 8/metabolismo , Morte Celular , Células Epiteliais/metabolismo , Proteína de Domínio de Morte Associada a Fas/genética , Proteína de Domínio de Morte Associada a Fas/metabolismo , Homeostase , Inflamação , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas de Ligação a Fosfato , Proteínas Quinases
18.
Front Immunol ; 11: 536, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328060

RESUMO

Efficient induction of effector and long-term protective antigen-specific CD8+ T memory response by vaccination is essential to eliminate malignant and pathogen-infected cells. Intracellular infectious bacteria, including Listeria monocytogenes, have been considered potent vectors to carry multiple therapeutic proteins and generate antigen-specific CD8+ T cell responses. Although the role of molecules involved in inflammatory cell death pathways, such as necroptosis (RIPK3-mediated) and pyroptosis (Caspase-1/11-mediated), as effectors of immune response against intracellular bacteria are relatively well understood, their contribution to the adjuvant effect of recombinant bacterial vectors in the context of antigen-specific CD8+ T cell response remained obscure. Therefore, we evaluated the impact of RIPK3 and Caspase-1/11 (Casp-1/11) individual and combined deficiencies on the modulation of antigen-specific CD8+ T cell response during vaccination of mice with ovalbumin-expressing L. monocytogenes (LM-OVA). We observed that Casp-1/11 but not RIPK3 deficiency negatively impacts the capacity of mice to clear LM-OVA. Importantly, both RIPK3 and Casp-1/11 are necessary for optimal LM-OVA-mediated antigen-specific CD8+ T cell response, as measured by in vivo antigen-specific CD8+ T cell proliferation, target cell elimination, and cytokine production. Furthermore, Casp-1/11 and Casp-1/11/RIPK3 combined deficiencies restrict the early initiation of antigen-specific CD8+ T cell memory response. Taken together, our findings demonstrate that RIPK3 and Casp-1/11 influence the quality of CD8+ T cell responses induced by recombinant L. monocytogenes vectors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Caspase 1/imunologia , Caspases Iniciadoras/imunologia , Vetores Genéticos/imunologia , Listeria monocytogenes/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/imunologia , Animais , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
19.
Cells ; 9(4)2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283822

RESUMO

Annexin A1 (AnxA1) is a potent anti-inflammatory protein that downregulates proinflammatory cytokine release. This study evaluated the role of AnxA1 in the regulation of NLRP3 inflammasome activation and lipid release by starch-elicited murine peritoneal macrophages. C57bl/6 wild-type (WT) and AnxA1-null (AnxA1-/-) mice received an intraperitoneal injection of 1.5% starch solution for macrophage recruitment. NLRP3 was activated by priming cells with lipopolysaccharide for 3 h, followed by nigericin (1 h) or ATP (30 min) incubation. As expected, nigericin and ATP administration decreased elicited peritoneal macrophage viability and induced IL-1ß release, more pronounced in the AnxA1-/- cells than in the control peritoneal macrophages. In addition, nigericin-activated AnxA1-/- macrophages showed increased levels of NLRP3, while points of co-localization of the AnxA1 protein and NLRP3 inflammasome were detected in WT cells, as demonstrated by ultrastructural analysis. The lipidomic analysis showed a pronounced release of prostaglandins in nigericin-stimulated WT peritoneal macrophages, while ceramides were detected in AnxA1-/- cell supernatants. Different eicosanoid profiles were detected for both genotypes, and our results suggest that endogenous AnxA1 regulates the NLRP3-derived IL-1ß and lipid mediator release in macrophages.


Assuntos
Anexina A1/metabolismo , Inflamassomos/metabolismo , Macrófagos Peritoneais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Anexina A1/imunologia , Inflamassomos/imunologia , Metabolismo dos Lipídeos , Macrófagos Peritoneais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
J Vis Exp ; (157)2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32250348

RESUMO

Astrocytes and microglia are the most abundant glial cells. They are responsible for physiological support and homeostasis maintenance in the central nervous system (CNS). The increasing evidences of their involvement in the control of infectious diseases justify the emerging interest in the improvement of methodologies to isolate primary astrocytes and microglia in order to evaluate their responses to infections that affect the CNS. Considering the impact of Trypanosoma cruzi (T. cruzi) and Toxoplasma gondii (T. gondii) infection in the CNS, here we provide a method to extract, maintain, dissociate and infect murine astrocytes and microglia cells with protozoa parasites. Extracted cells from newborn cortices are maintained in vitro for 14 days with periodic differential media replacement. Astrocytes and microglia are obtained from the same extraction protocol by mechanical dissociation. After phenotyping by flow cytometry, cells are infected with protozoa parasites. The infection rate is determined by fluorescence microscopy at different time points, thus enabling the evaluation of differential ability of glial cells to control protozoan invasion and replication. These techniques represent simple, cheap and efficient methods to study the responses of astrocytes and microglia to infections, opening the field for further neuroimmunology analysis.


Assuntos
Astrócitos/citologia , Microglia/citologia , Doenças Parasitárias/patologia , Animais , Animais Recém-Nascidos , Astrócitos/parasitologia , Técnicas de Cultura de Células , Córtex Cerebral/citologia , Córtex Cerebral/parasitologia , Camundongos , Microglia/parasitologia , Doenças Parasitárias/parasitologia , Toxoplasma/fisiologia , Trypanosoma cruzi/fisiologia
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