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1.
Nat Commun ; 15(1): 2751, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553499

RESUMO

Influenza virus activates cellular inflammasome pathways, which can be both beneficial and detrimental to infection outcomes. Here, we investigate the function of the inflammasome-activated, pore-forming protein gasdermin D (GSDMD) during infection. Ablation of GSDMD in knockout (KO) mice (Gsdmd-/-) significantly attenuates influenza virus-induced weight loss, lung dysfunction, lung histopathology, and mortality compared with wild type (WT) mice, despite similar viral loads. Infected Gsdmd-/- mice exhibit decreased inflammatory gene signatures shown by lung transcriptomics. Among these, diminished neutrophil gene activation signatures are corroborated by decreased detection of neutrophil elastase and myeloperoxidase in KO mouse lungs. Indeed, directly infected neutrophils are observed in vivo and infection of neutrophils in vitro induces release of DNA and tissue-damaging enzymes that is largely dependent on GSDMD. Neutrophil depletion in infected WT mice recapitulates the reductions in mortality, lung inflammation, and lung dysfunction observed in Gsdmd-/- animals, while depletion does not have additive protective effects in Gsdmd-/- mice. These findings implicate a function for GSDMD in promoting lung neutrophil responses that amplify influenza virus-induced inflammation and pathogenesis. Targeting the GSDMD/neutrophil axis may provide a therapeutic avenue for treating severe influenza.


Assuntos
Neutrófilos , Orthomyxoviridae , Animais , Camundongos , Neutrófilos/metabolismo , Gasderminas , Inflamassomos/genética , Inflamassomos/metabolismo , Inflamação/genética , Inflamação/metabolismo , Orthomyxoviridae/metabolismo , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(51): e2300474120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38100417

RESUMO

Seasonal influenza results in 3 to 5 million cases of severe disease and 250,000 to 500,000 deaths annually. Macrophages have been implicated in both the resolution and progression of the disease, but the drivers of these outcomes are poorly understood. We probed mouse lung transcriptomic datasets using the Digital Cell Quantifier algorithm to predict immune cell subsets that correlated with mild or severe influenza A virus (IAV) infection outcomes. We identified a unique lung macrophage population that transcriptionally resembled small serosal cavity macrophages and whose presence correlated with mild disease. Until now, the study of serosal macrophage translocation in the context of viral infections has been neglected. Here, we show that pleural macrophages (PMs) migrate from the pleural cavity to the lung after infection with IAV. We found that the depletion of PMs increased morbidity and pulmonary inflammation. There were increased proinflammatory cytokines in the pleural cavity and an influx of neutrophils within the lung. Our results show that PMs are recruited to the lung during IAV infection and contribute to recovery from influenza. This study expands our knowledge of PM plasticity and identifies a source of lung macrophages independent of monocyte recruitment and local proliferation.


Assuntos
Vírus da Influenza A , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Camundongos , Humanos , Influenza Humana/genética , Pulmão , Macrófagos , Macrófagos Alveolares
3.
J Food Sci ; 88(12): 4928-4941, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905708

RESUMO

This study validated an analytical technique using headspace gas chromatography with flame ionization detection to quantify acrylonitrile monomer with a quantification limit of 0.10 ± 0.04 µg kg-1 . Subsequently, the acrylonitrile migration from polypropylene granules was evaluated in food simulants water and ethanol (50% v/v) and at two temperatures (20 ± 1°C and 44 ± 2°C) for up to 6 weeks, representing the service time of a bottle. From the experimental data obtained, pseudo-second-order kinetics were adjusted to represent the acrylonitrile migration into the simulants. For water, equilibrium concentrations of 13.58 and 16.58 µg kg-1 at 20 and 44°C, respectively, were obtained, while for 50% ethanol, 15.07 and 16.40 µg kg-1 were obtained for the same temperatures. The experimental results and the values estimated from the migration kinetics indicate that the maximum acrylonitrile concentration will not exceed the tolerable specific limit established in regulations. PRACTICAL APPLICATION: The migration of compounds such as acrylonitrile can be a drawback resulting in an undesirable reduction in the shelf life of liquid foods packaged in bottles made of materials such as polypropylene. In this paper, acrylonitrile migration kinetics and a methodology are proposed to determine whether the tolerable migration limits are ever reached, which can serve as a tool for producers of this type of packaging of food to predict shelf life.


Assuntos
Acrilonitrila , Embalagem de Alimentos , Polipropilenos , Acrilonitrila/análise , Etanol/química , Água/química , Contaminação de Alimentos/análise
4.
Immunohorizons ; 7(6): 431-441, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37289499

RESUMO

IL-35 is an immunosuppressive cytokine with roles in cancer, autoimmunity, and infectious disease. In the conventional model of IL-35 biology, the p35 and Ebi3 domains of this cytokine interact with IL-12Rß2 and gp130, respectively, on the cell surface of regulatory T and regulatory B cells, triggering their suppression of Th cell activity. Here we use a human IL-12 bioactivity reporter cell line, protein binding assays, and primary human Th cells to demonstrate an additional mechanism by which IL-35 suppresses Th cell activity, wherein IL-35 directly inhibits the association of IL-12 with its surface receptor IL-12Rß2 and downstream IL-12-dependent activities. IL-12 binding to the surface receptor IL-12Rß1 was unaffected by IL-35. These data demonstrate that in addition to acting via regulatory T and regulatory B cells, human IL-35 can also directly suppress IL-12 bioactivity and its interaction with IL-12Rß2.


Assuntos
Interleucina-12 , Interleucinas , Humanos , Interleucina-12/metabolismo , Ligação Proteica , Interleucinas/metabolismo , Citocinas/metabolismo , Linhagem Celular
5.
J Immunol ; 209(5): 845-854, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36130131

RESUMO

Retinoic acid-inducible gene I-like receptors (RLRs) are cytosolic RNA sensors critical for initiation of antiviral immunity. Activation of RLRs following RNA recognition leads to production of antiviral genes and IFNs for induction of broad antiviral immunity. Although the RLRs are ubiquitously expressed, much of our understanding of these molecules comes from their study in epithelial cells and fibroblasts. However, RLR activation is critical for induction of immune function and long-term protective immunity. Recent work has focused on the roles of RLRs in immune cells and their contribution to programming of effective immune responses. This new understanding of RLR function in immune cells and immune programming has led to the development of vaccines and therapeutics targeting the RLRs. This review covers recent advances in our understanding of the contribution of RLRs to immune cell function during infection and the emerging RLR-targeting strategies for induction of immunity against cancer and viral infection.


Assuntos
RNA Helicases DEAD-box , Transdução de Sinais , Antivirais , Proteína DEAD-box 58 , RNA Helicases DEAD-box/metabolismo , Imunidade Inata , RNA , Tretinoína
6.
Biomedica ; 42(2): 342-354, 2022 06 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35867926

RESUMO

Introduction: Hyperthyroidism is a heterogeneous condition characterized by the excessive production of thyroid hormones. It represents a diagnostic and therapeutic challenge. Objective: To describe the clinical and paraclinical characteristics and the evolution and differences between the main etiologies in patients with hyperthyroidism treated by the Pediatric Endocrinology Service at the Hospital Universitario San Vicente Fundación in Medellín, Colombia, between July 1st., 2015, and June 30th., 2020. Materials and methods: We conducted a cross-sectional observational study with retrospective data collection. Results: We included 54 patients with a mean age of 11.9 years, 72.2% of whom were female; 85.2% had no history of comorbidities related to autoimmunity; 11.1% had a family history of Graves' disease, and 29.6% of other thyroid diseases. Goiter was the most frequent clinical manifestation (83.3%) and 92.6% of the patients received treatment with methimazole, 79.6% required beta-blockers, and 11.2% additional drug therapy. Adverse drug reactions occurred in 16.7% of the patients and in 20.4% there was a resolution of hyperthyroidism (spontaneous: 9.3%; after radio-iodine ablation: 9.3%, and after surgery: 1.9%). Conclusion: Hyperthyroidism is a disease with diverse clinical manifestations. Its most frequent cause is Graves' disease followed by hashitoxicosis, which in this study had a higher frequency than that reported in the literature. The duration and side effects of pharmacological treatment were similar to those previously reported, but the higher frequency of agranulocytosis is noteworthy.


Introducción. El hipertiroidismo es una condición heterogénea caracterizada por la producción excesiva de hormonas tiroideas. Su aparición en la edad pediátrica representa un reto diagnóstico y terapéutico. Objetivo. Describir las características clínicas y paraclínicas, así como la evolución y las diferencias entre las principales causas etiológicas de los pacientes con hipertiroidismo atendidos por el Servicio de Endocrinología Pediátrica del Hospital Universitario San Vicente Fundación en Medellín, Colombia, entre el 1° de julio de 2015 y el 30 de junio de 2020. Materiales y métodos. Se hizo un estudio observacional transversal con recolección retrospectiva de la información. Resultados. Se incluyeron 54 pacientes con una edad media de 11,9 años, 72,2 % de ellos mujeres. El 11,1 % tenía antecedentes familiares de enfermedad de Graves y 29,6 % de otras enfermedades tiroideas. El bocio fue la manifestación clínica más frecuente (83,3 %). El 92,6 % había recibido terapia con metimazol, el 79,6 % requirió betabloqueador y el 11,2 % necesitó una terapia farmacológica adicional. Se presentaron reacciones adversas a la medicación en el 16,7 %. En el 20,4 % de los pacientes hubo resolución del hipertiroidismo (espontánea: 9,3 %; posterior a la ablación con yodo radiactivo: 9,3 %, y después de la cirugía: 1,9 %). Conclusión. El hipertiroidismo es una enfermedad con manifestaciones clínicas diversas. La causa más frecuente es la enfermedad de Graves, seguida por la hashitoxicosis. En este estudio, la hashitoxicosis fue más frecuente que en estudios previos. La duración y los efectos secundarios del tratamiento farmacológico fueron similares a los reportados previamente, pero es de resaltar la mayor frecuencia de agranulocitosis en nuestra población.


Assuntos
Hospitais , Colômbia , Estudos Retrospectivos
7.
J Immunol ; 208(2): 247-256, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35017214

RESUMO

IFNs are comprised of three families of cytokines that confer protection against pathogen infection and uncontrolled cellular proliferation. The broad role IFNs play in innate and adaptive immune regulation has placed them under heavy scrutiny to position them as "friend" or "foe" across pathologies. Genetic lesions in genes involving IFN synthesis and signaling underscore the disparate outcomes of aberrant IFN signaling. Abrogation of the response leads to susceptibility to microbial infections whereas unabated IFN induction underlies a variety of inflammatory diseases and tumor immune evasion. Type I and III IFNs have overlapping roles in antiviral protection, yet the mechanisms by which they are induced and promote the expression of IFN-stimulated genes and inflammation can distinguish their biological functions. In this review, we examine the molecular factors that shape the shared and distinct roles of type I and III IFNs in immunity.


Assuntos
Interferon Tipo I/imunologia , Interferons/imunologia , Viroses/imunologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Humanos , Inflamação/imunologia , Interferon Tipo I/metabolismo , Interferon Tipo I/uso terapêutico , Interferons/metabolismo , Interferons/uso terapêutico , Transdução de Sinais/imunologia , Ativação Transcricional/genética , Ativação Transcricional/imunologia , Interferon lambda
8.
Blood ; 138(8): 722-737, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34436524

RESUMO

Immunopathology and intestinal stem cell (ISC) loss in the gastrointestinal (GI) tract is the prima facie manifestation of graft-versus-host disease (GVHD) and is responsible for significant mortality after allogeneic bone marrow transplantation (BMT). Approaches to prevent GVHD to date focus on immune suppression. Here, we identify interferon-λ (IFN-λ; interleukin-28 [IL-28]/IL-29) as a key protector of GI GVHD immunopathology, notably within the ISC compartment. Ifnlr1-/- mice displayed exaggerated GI GVHD and mortality independent of Paneth cells and alterations to the microbiome. Ifnlr1-/- intestinal organoid growth was significantly impaired, and targeted Ifnlr1 deficiency exhibited effects intrinsic to recipient Lgr5+ ISCs and natural killer cells. PEGylated recombinant IL-29 (PEG-rIL-29) treatment of naive mice enhanced Lgr5+ ISC numbers and organoid growth independent of both IL-22 and type I IFN and modulated proliferative and apoptosis gene sets in Lgr5+ ISCs. PEG-rIL-29 treatment improved survival, reduced GVHD severity, and enhanced epithelial proliferation and ISC-derived organoid growth after BMT. The preservation of ISC numbers in response to PEG-rIL-29 after BMT occurred both in the presence and absence of IFN-λ-signaling in recipient natural killer cells. IFN-λ is therefore an attractive and rapidly testable approach to prevent ISC loss and immunopathology during GVHD.


Assuntos
Transplante de Medula Óssea , Citocinas/farmacologia , Gastroenteropatias , Doença Enxerto-Hospedeiro , Interleucinas/farmacocinética , Transdução de Sinais , Animais , Citocinas/imunologia , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/genética , Gastroenteropatias/imunologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/imunologia , Interleucinas/imunologia , Camundongos , Camundongos Knockout , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Transplante Homólogo
9.
JCI Insight ; 6(1)2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33232305

RESUMO

Cardiopulmonary bypass (CPB) is required during most cardiac surgeries. CBP drives systemic inflammation and multiorgan dysfunction that is especially severe in neonatal patients. Limited understanding of molecular mechanisms underlying CPB-associated inflammation presents a significant barrier to improve clinical outcomes. To better understand these clinical issues, we performed mRNA sequencing on total circulating leukocytes from neonatal patients undergoing CPB. Our data identify myeloid cells, particularly monocytes, as the major cell type driving transcriptional responses to CPB. Furthermore, IL-8 and TNF-α were inflammatory cytokines robustly upregulated in leukocytes from both patients and piglets exposed to CPB. To delineate the molecular mechanism, we exposed THP-1 human monocytic cells to CPB-like conditions, including artificial surfaces, high shear stress, and cooling/rewarming. Shear stress was found to drive cytokine upregulation via calcium-dependent signaling pathways. We also observed that a subpopulation of THP-1 cells died via TNF-α-mediated necroptosis, which we hypothesize contributes to post-CPB inflammation. Our study identifies a shear stress-modulated molecular mechanism that drives systemic inflammation in pediatric CPB patients. These are also the first data to our knowledge to demonstrate that shear stress causes necroptosis. Finally, we observe that calcium and TNF-α signaling are potentially novel targets to ameliorate post-CPB inflammation.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Citocinas/genética , Monócitos/imunologia , Monócitos/patologia , Animais , Animais Recém-Nascidos , Sinalização do Cálcio , Citocinas/biossíntese , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Mediadores da Inflamação/metabolismo , Interleucina-8/biossíntese , Interleucina-8/genética , Masculino , Modelos Animais , Monócitos/fisiologia , Necroptose/genética , Necroptose/fisiologia , RNA-Seq , Estresse Mecânico , Sus scrofa , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Síndrome de Resposta Inflamatória Sistêmica/genética , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Células THP-1 , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Regulação para Cima
10.
Nat Immunol ; 20(12): 1610-1620, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31740798

RESUMO

The initial response to viral infection is anticipatory, with host antiviral restriction factors and pathogen sensors constantly surveying the cell to rapidly mount an antiviral response through the synthesis and downstream activity of interferons. After pathogen clearance, the host's ability to resolve this antiviral response and return to homeostasis is critical. Here, we found that isoforms of the RNA-binding protein ZAP functioned as both a direct antiviral restriction factor and an interferon-resolution factor. The short isoform of ZAP bound to and mediated the degradation of several host interferon messenger RNAs, and thus acted as a negative feedback regulator of the interferon response. In contrast, the long isoform of ZAP had antiviral functions and did not regulate interferon. The two isoforms contained identical RNA-targeting domains, but differences in their intracellular localization modulated specificity for host versus viral RNA, which resulted in disparate effects on viral replication during the innate immune response.


Assuntos
Infecções por Alphavirus/imunologia , Interferons/genética , Isoformas de Proteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Proteínas Repressoras/metabolismo , Sindbis virus/fisiologia , Infecções por Alphavirus/genética , Retroalimentação Fisiológica , Células HEK293 , Células Hep G2 , Homeostase , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Ligação Proteica , Isoformas de Proteínas/genética , RNA/genética , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Proteínas Repressoras/genética , Replicação Viral
11.
Immunity ; 51(3): 451-464.e6, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31471108

RESUMO

Type I and III interferons (IFNs) activate similar downstream signaling cascades, but unlike type I IFNs, type III IFNs (IFNλ) do not elicit strong inflammatory responses in vivo. Here, we examined the molecular mechanisms underlying this disparity. Type I and III IFNs displayed kinetic differences in expression of IFN-stimulated genes and proinflammatory responses, with type I IFNs preferentially stimulating expression of the transcription factor IRF1. Type III IFNs failed to induce IRF1 expression because of low IFNλ receptor abundance and insufficient STAT1 activation on epithelial cells and thus did not activate the IRF1 proinflammatory gene program. Rather, IFNλ stimulation preferentially induced factors implicated in tissue repair. Our findings suggest that IFN receptor compartmentalization and abundance confer a spatiotemporal division of labor where type III IFNs control viral spread at the site of the infection while restricting tissue damage; the transient induction of inflammatory responses by type I IFNs recruits immune effectors to promote protective immunity.


Assuntos
Fator Regulador 1 de Interferon/imunologia , Interferon Tipo I/imunologia , Interferons/imunologia , Animais , Linhagem Celular , Células Epiteliais/imunologia , Humanos , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Transcrição STAT1/imunologia , Interferon lambda
12.
Orinoquia ; 23(1): 31-40, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1091570

RESUMO

Resumen El bagre marino Ariopsis seemanni es aprovechado como pez de consumo en la alimentación de pescadores y pobladores de la región pacifica colombiana y como pez ornamental (5 a 10 cm -longitud total), a nivel comercial nacional e internacional. En Colombia esta especie ha sido priorizada en la agenda nacional de investigación en acuicultura de 2011-2012, como una de las especies marinas potenciales en actividades acuícolas. El objetivo de esta investigación fue evaluar el efecto de la gonadotropina coriónica humana (HGC) y el extracto pituitario de carpa (EPC) sobre la maduración final y el desove en hembras adultas de la especie. Se utilizaron 24 parejas de peces silvestres capturadas del medio, con un peso promedio de 263.6±42.2 g y 174.4±30.4 g para hembras y machos, respectivamente. Se utilizaron cuatro tratamientos hormonales: T1: 5 mg EPC/kg; T2: 7 mg EPC/kg; T3: 2000 UI HGC/kg y T4: 1000 UI HGC/kg. Se identificaron tres tipos de oocitos en maduración, no se presentaron diferencias estadísticamente significativas (p>0,05) entre los tratamientos utilizados y la cantidad de oocitos en maduración; no se obtuvo desove espontaneo en ninguna de las hembras inducidas con las dosis hormonales empleadas.


Abstract The tete sea catfish Ariopsis seemanni is a fish used for human consumption by fishermen and residents along the coast of Colombia and as ornamental fish (5 to 10 cm -total longitude), at national and international comercial level. In Colombia, this species has been prioritized in the national aquaculture research agenda 2011-2012, as one of the potential marine species for aquaculture activities. This research was aimed at evaluating the effect of human chorionic gonadotropin (HGC) and carp pituitary extract (EPC) on final maturation and spawning adult females of the species. 24 pairs of wild fish were used, with an average weight of 263.6±42.2 g and 174.4±30.4 g for females and males, respectively. Four hormonal treatments was be used: T1: EPC 5 mg/kg; T2: EPC 7 mg/kg; T3: HGC 2000 IU/kg and T4: HGC 1000 IU/kg. Identify three types of maturation oocytes was. There were no statistically significant differences (p>0,05) between treatments used and the number of oocytes achieving maturation. No spontaneous spawning was obtained in any of the females induced with the hormonal doses used.


Resumo O bagre marino Ariopsis seemanni é aproveitado como peixe de consumo na alimentação de pescadores e moradores da região pacifica colombiana e como peixe ornamental (5 a 10 cm de comprimento), a nível comercial nacional e internacional. Na Colômbia A. seemanni tem sido priorizado na agenda nacional de pesquisa na aquicultura de 2011-2012, como uma das espécies marinhas potenciais em atividades aquícolas. Esta pesquisa teve como objetivo avaliar o efeito da gonadotrofina coriónica humana (GCH) e o extrato pituitário de carpa (EPC) sobre a maduração final e o desove em fêmeas adultas desta espécie. Utilizaram-se 24 casais de peixes retirados do meio natural, com um peso médio de 263,6 ± 42,2 g e 174,4 ± 30,4 g para fêmeas e machos, respectivamente. Empregaram-se quatro tratamentos hormonais: T1: 5 mg EPC/kg; T2: 7 mg EPC/kg; T3: 2000 UI HGC/kg e T4: 1000 UI HGC/kg. Identificaram-se três tipos de oócitos em maduração, não houve diferencias estatisticamente significativas (p>0,05) entre os tratamentos utilizados e a quantidade de oócitos em maturação; não foi possível obter desove espontâneo em nenhuma das fêmeas induzidas com as doses hormonais empregadas.

13.
Vaccine ; 35(45): 6112-6121, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28967519

RESUMO

The host innate immune response to influenza virus is a key determinant of pathogenic outcomes and long-term protective immune responses against subsequent exposures. Here, we present a direct contrast of the host responses in primary differentiated human nasal epithelial cell (hNEC) cultures following infection with either a seasonal H3N2 influenza virus (WT) or the antigenically-matched live-attenuated vaccine (LAIV) strain. Comparison of the transcriptional profiles obtained 24 and 36h post-infection showed that the magnitude of gene expression was greater in LAIV infected relative to that observed in WT infected hNEC cultures. Functional enrichment analysis revealed that the antiviral and inflammatory responses were largely driven by type III IFN induction in both WT and LAIV infected cells. However, the enrichment of biological pathways involved in the recruitment of mononuclear leukocytes, antigen-presenting cells, and T lymphocytes was uniquely observed in LAIV infected cells. These observations were reflective of the host innate immune responses observed in individuals acutely infected with influenza viruses. These findings indicate that cell-intrinsic type III IFN-mediated innate immune responses in the nasal epithelium are not only crucial for viral clearance and attenuation, but may also play an important role in the induction of protective immune responses with live-attenuated vaccines.


Assuntos
Células Epiteliais/imunologia , Imunidade Inata/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Mucosa Nasal/imunologia , Vacinas Atenuadas/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Linhagem Celular , Cães , Células Epiteliais/virologia , Humanos , Vírus da Influenza A Subtipo H3N2/imunologia , Leucócitos Mononucleares , Células Madin Darby de Rim Canino , Mucosa Nasal/virologia , Linfócitos T/imunologia
14.
J Virol ; 91(11)2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28331091

RESUMO

Ebola virus (EBOV) and Reston virus (RESTV) are members of the Ebolavirus genus which greatly differ in their pathogenicity. While EBOV causes a severe disease in humans characterized by a dysregulated inflammatory response and elevated cytokine and chemokine production, there are no reported disease-associated human cases of RESTV infection, suggesting that RESTV is nonpathogenic for humans. The underlying mechanisms determining the pathogenicity of different ebolavirus species are not yet known. In this study, we dissected the host response to EBOV and RESTV infection in primary human monocyte-derived macrophages (MDMs). As expected, EBOV infection led to a profound proinflammatory response, including strong induction of type I and type III interferons (IFNs). In contrast, RESTV-infected macrophages remained surprisingly silent. Early activation of IFN regulatory factor 3 (IRF3) and NF-κB was observed in EBOV-infected, but not in RESTV-infected, MDMs. In concordance with previous results, MDMs treated with inactivated EBOV and Ebola virus-like particles (VLPs) induced NF-κB activation mediated by Toll-like receptor 4 (TLR4) in a glycoprotein (GP)-dependent manner. This was not the case in cells exposed to live RESTV, inactivated RESTV, or VLPs containing RESTV GP, indicating that RESTV GP does not trigger TLR4 signaling. Our results suggest that the lack of immune activation in RESTV-infected MDMs contributes to lower pathogenicity by preventing the cytokine storm observed in EBOV infection. We further demonstrate that inhibition of TLR4 signaling abolishes EBOV GP-mediated NF-κB activation. This finding indicates that limiting the excessive TLR4-mediated proinflammatory response in EBOV infection should be considered as a potential supportive treatment option for EBOV disease.IMPORTANCE Emerging infectious diseases are a major public health concern, as exemplified by the recent devastating Ebola virus (EBOV) outbreak. Different ebolavirus species are associated with widely varying pathogenicity in humans, ranging from asymptomatic infections for Reston virus (RESTV) to severe disease with fatal outcomes for EBOV. In this comparative study of EBOV- and RESTV-infected human macrophages, we identified key differences in host cell responses. Consistent with previous data, EBOV infection is associated with a proinflammatory signature triggered by the surface glycoprotein (GP), which can be inhibited by blocking TLR4 signaling. In contrast, infection with RESTV failed to stimulate a strong host response in infected macrophages due to the inability of RESTV GP to stimulate TLR4. We propose that disparate proinflammatory host signatures contribute to the differences in pathogenicity reported for ebolavirus species and suggest that proinflammatory pathways represent an intriguing target for the development of novel therapeutics.


Assuntos
Ebolavirus/imunologia , Ebolavirus/patogenicidade , Interações Hospedeiro-Patógeno , Macrófagos/virologia , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Quimiocinas/imunologia , Quimiocinas/metabolismo , Chlorocebus aethiops , Citocinas/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Ebolavirus/fisiologia , Perfilação da Expressão Gênica , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/imunologia , Interferons/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Células Vero , Virulência
15.
Immunity ; 40(6): 936-48, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24931123

RESUMO

Virus infection is sensed in the cytoplasm by retinoic acid-inducible gene I (RIG-I, also known as DDX58), which requires RNA and polyubiquitin binding to induce type I interferon (IFN) and activate cellular innate immunity. We show that the human IFN-inducible oligoadenylate synthetases-like (OASL) protein has antiviral activity and mediates RIG-I activation by mimicking polyubiquitin. Loss of OASL expression reduced RIG-I signaling and enhanced virus replication in human cells. Conversely, OASL expression suppressed replication of a number of viruses in a RIG-I-dependent manner and enhanced RIG-I-mediated IFN induction. OASL interacted and colocalized with RIG-I, and through its C-terminal ubiquitin-like domain specifically enhanced RIG-I signaling. Bone-marrow-derived macrophages from mice deficient for Oasl2 showed that among the two mouse orthologs of human OASL, Oasl2 is functionally similar to human OASL. Our findings show a mechanism by which human OASL contributes to host antiviral responses by enhancing RIG-I activation.


Assuntos
2',5'-Oligoadenilato Sintetase/imunologia , RNA Helicases DEAD-box/imunologia , Infecções por Vírus de DNA/imunologia , Interferon Tipo I/imunologia , Infecções por Vírus de RNA/imunologia , 2',5'-Oligoadenilato Sintetase/genética , Animais , Proteína DEAD-box 58 , Células HCT116 , Células HEK293 , Humanos , Imunidade Inata , Fator Regulador 7 de Interferon/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Poliubiquitina , Ligação Proteica/imunologia , Interferência de RNA , RNA Interferente Pequeno , Receptores Imunológicos , Transdução de Sinais/imunologia , Replicação Viral/imunologia
16.
Virology ; 458-459: 4-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24928034

RESUMO

Primary effusion lymphoma (PEL), associated with the latent infection by KSHV, constitutively expresses interferon-regulatory factor 4 (IRF4). We recently showed that IRF4 differentially regulates expression of cellular interferon-stimulated genes (ISGs) and viral genes (Forero et al., 2013). Here, using inducible IRF4 knockdown, we demonstrate that IRF4 silencing results in enhanced transcription of KSHV replication transactivator RTA. As a result viral transcription is increased leading to virus reactivation. Taken together, our results show that IRF4 helps maintain the balance between latency and KSHV reactivation in PEL cells.


Assuntos
Herpesvirus Humano 8/fisiologia , Fatores Reguladores de Interferon/metabolismo , Latência Viral/fisiologia , Linhagem Celular , Regulação para Baixo , Inativação Gênica , Humanos , Fatores Reguladores de Interferon/genética
17.
J Immunol ; 192(12): 5933-42, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24799566

RESUMO

Polyomaviruses encode a large T Ag (LT), a multifunctional protein essential for the regulation of both viral and host cell gene expression and productive viral infection. Previously, we have shown that stable expression of LT protein results in upregulation of genes involved in the IFN induction and signaling pathway. In this study, we focus on the cellular signaling mechanism that leads to the induction of IFN responses by LT. Our results show that ectopic expression of SV40 LT results in the induction of IFN-stimulated genes (ISGs) in human fibroblasts and confers an antiviral state. We describe a LT-initiated DNA damage response (DDR) that activates IFN regulatory factor 1, causing IFN-ß production and consequent ISG expression in human cells. This IFN-ß and ISG induction is dependent on ataxia-telangiectasia mutated and Rad3-related (ATR) kinase, but independent of ATM. ATR kinase inhibition using a selective kinase inhibitor (ETP-46464) caused a decrease in IFN regulatory factor 1 stabilization and ISG expression. Furthermore, expression of a mutant LT that does not induce DDR also does not induce IFN-ß and ISGs. These results show that, in the absence of viral infection, LT-initiated activation of ATR-dependent DDR is sufficient for the induction of an IFN-ß-mediated innate immune response in human cells. Thus, we have uncovered a novel and critical role for ATR as a mediator of antiviral responses utilizing LT.


Assuntos
Antígenos Transformantes de Poliomavirus/imunologia , Dano ao DNA/imunologia , Fator Regulador 1 de Interferon/imunologia , Interferon beta/imunologia , Vírus 40 dos Símios/imunologia , Antígenos Transformantes de Poliomavirus/genética , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/imunologia , Dano ao DNA/genética , Células HEK293 , Humanos , Fator Regulador 1 de Interferon/genética , Interferon beta/genética , Inibidores de Proteínas Quinases/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Vírus 40 dos Símios/genética
18.
J Immunol ; 191(3): 1476-85, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23804715

RESUMO

IFN regulatory factor (IRF) 4 is a hematopoietic cell-specific transcription factor that regulates the maturation and differentiation of immune cells. Using an inducible expression system, we found that IRF4 directly induced a specific subset of IFN-stimulated genes (ISGs) in a type I IFN-independent manner in both epithelial and B cell lines. Moreover, Kaposi sarcoma-associated herpesvirus (KSHV)-encoded viral FLICE inhibitory protein (vFLIP) enhances IRF4-mediated gene induction. Coexpression of IRF4 with vFLIP significantly increased ISG60 (IFIT3) and Cig5 (RSAD2) transcription that was dependent on the ability of vFLIP to activate NF-κB. A vFLIP mutant (A57L) defective in NF-κB activation failed to enhance IRF4-mediated ISG induction. Thus, we provide a physiologically relevant mechanism by which viral protein-mediated NF-κB activation modulates specific ISG induction by IRF4. In contrast, IRF4 also acted as a negative regulator of KSHV replication and transcription activator expression after induction of KSHV lytic reactivation in KSHV-positive primary effusion lymphoma cells. Taken together, these results suggest a dual role for IRF4 in regulating ISG induction and KSHV lytic reactivation in primary effusion lymphoma cells.


Assuntos
Herpesvirus Humano 8/metabolismo , Fatores Reguladores de Interferon/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Linhagem Celular Transformada , Ativação Enzimática/genética , Expressão Gênica , Regulação da Expressão Gênica , Células HEK293 , Herpesvirus Humano 8/genética , Humanos , Interferon Tipo I , Linfoma/genética , Linfoma/virologia , Mutação , NF-kappa B/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Transcrição Gênica/genética , Ativação Transcricional , Latência Viral , Replicação Viral/genética
19.
Adv Virol ; 2012: 815465, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22924042

RESUMO

Successful oncolytic virus treatment of malignant glioblastoma multiforme depends on widespread tumor-specific lytic virus replication and escape from mitigating innate immune responses to infection. Here we characterize a new HSV vector, JD0G, that is deleted for ICP0 and the joint sequences separating the unique long and short elements of the viral genome. We observed that JD0G replication was enhanced in certain glioblastoma cell lines compared to HEL cells, suggesting that a vector backbone deleted for ICP0 may be useful for treatment of glioblastoma. The innate immune response to virus infection can potentially impede oncolytic vector replication in human tumors. Indoleamine-2,3-dioxygenase (IDO) is expressed in response to interferon γ (IFNγ) and has been linked to both antiviral functions and to the immune escape of tumor cells. We observed that IFNγ treatment of human glioblastoma cells induced the expression of IDO and that this expression was quelled by infection with both wild-type and JD0G viruses. The role of IDO in inhibiting virus replication and the connection of this protein to the escape of tumor cells from immune surveillance suggest that IDO downregulation by HSV infection may enhance the oncolytic activity of vectors such as JD0G.

20.
Rev. cienc. salud (Bogotá) ; 10(supl.1): 29-41, mar. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-656911

RESUMO

Objetivo: considerando el elevado uso de plaguicidas en Colombia y los efectos nocivos que produce la exposición a estas sustancias para la salud humana y el ambiente, se realizó un estudio para la determinación de biomarcadores de exposición y efecto de plaguicidas en la población de Suesca que habita en la ribera del río Bogotá, de los niveles de plaguicidas en muestras de agua del río tomadas en el mismo municipio y en muestras de pez "Capitán de la sabana" (Eremophylus mutisii) capturado en dicha zona. Materiales y métodos: se realizaron determinaciones para organofosforados, carbamatos, ditiocarbamatos y organoclorados También se exploró, mediante una encuesta, la exposición ocupacional a plaguicidas y el conocimiento y utilización de medidas de protección personal en su actividad laboral. Adicionalmente, se examinó el hábito de la pesca de pez Capitán y su consumo en la dieta de los habitantes de esta zona del río. Resultados: los resultados muestran la presencia de plaguicidas organoclorados y organofosforados en el río y en el tejido de los peces y organoclorados y etilentiourea en las muestras biológicas humanas. En el estudio participaron trabajadores directamente expuestos a plaguicidas, quienes manipulan productos de alta toxicidad; en su mayoría conocen y emplean las medidas de protección personal e higiene industrial. Conclusiones: existe contaminación por plaguicidas en la cuenca alta del río Bogotá que afecta a la fauna y a las poblaciones ribereñas. Es necesario promover mejores medidas para el cuidado del ambiente, para la protección y para el autocuidado de las personas que manipulan plaguicidas en la zona.


Objective: Considering the high use of pesticides in Colombia and the harmful effects resulting from exposure to these substances on human health and the environment, a study for the determination of biomarkers of exposure and effect of pesticides in population of the banks of the Río Bogotá in Suesca, the levels of pesticides in river water samples taken in the same city and in samples of fish, "Capitán de la Sabana" (Eremophylus mutisii) caught in this area. Materials and methods: We measured for organophosphates, carbamates, dithiocarbamates and organochlorines. We also explored through a survey of occupational exposure to pesticides in the population and knowledge and use of personal protective measures in their work. Additionally, we explored the habit of fishing for captain and consumption in the diet of the inhabitants of the riverbank. Results: The results show the presence of organochlorine and organophosphorus pesticides in the river and in fish tissue and organochlorine and ethylene thiourea in human biological samples. Participated in the study workers directly exposed to pesticides, highly toxic handlers, most know and use personal protective measures and industrial hygiene. Conclusions: Pollution such as pesticides in the upper basin of Bogotá that affects wildlife and coastal populations. Best action is necessary to promote environmental care, protection and self-care of persons using pesticides in the area.


Objetivos: Considerando o elevado uso de praguicidas na Colômbia e os efeitos nocivos que produz a exposição a estas sustancias para a saúde humana e o ambiente, se realizou um estudo para a determinação de biomarcadores de exposição e efeito de praguicidas na população de Suesca que habita na ribeira do rio Bogotá, dos níveis de praguicidas em amostras de água do rio tomadas no mesmo município e em amostras do peixe "Capitan de la sabana" (Eremophylus mutisii) caçado nesta zona. Materiais e métodos: se realizaram determinações para organofosforados, carbamates, ditiocarbamatos e organoclorados. Também explorou-se, mediante uma pesquisa, a exposição ocupacional a praguicidas e o conhecimento e utilização de medidas de proteção pessoal em sua atividade laboral. Adicionalmente, examinou-se o hábito da pesca de peixe "Capitan de la sabana" e seu consumo na dieta dos habitantes desta zona do rio. Resultados: os resultados mostram a presencia de praguicidas organoclorados e organofosforados no rio e no tecido dos peixes e organoclorados e etilentiouréia nas amostras biológicas humanas. No estudo participaram trabalhadores diretamente expostos a praguicidas, os quais manipulam produtos de alta toxicidade; na sua maioria conhecem e empregam as medidas de proteção pessoal e higiene industrial. Conclusões: existe contaminação por praguicidas na bacia alta do rio Bogotá que afeita à fauna e às populações da ribeira. É necessário promover melhores medidas para o cuidado do ambiente, para a proteção e para o autocuidado das pessoas que manipulam praguicidas na zona.


Assuntos
Humanos , Animais , Saúde Ambiental , Praguicidas , Medidas de Segurança , Poluição da Água , Biomarcadores , Saúde Ocupacional , Colômbia , Impactos da Poluição na Saúde , Exposição a Praguicidas , Fatores de Proteção , Meio Ambiente , Poluição Ambiental , Toxicidade , Peixes
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