RESUMO
Ineffective recovery from pneumonia can lead to interstitial lung disease characterized by aberrant epithelial cells in fibrotic regions. In this issue of the JCI, Lin et al. define molecular pathways leading to the development and persistence of keratin 5+ (Krt5+) epithelial cells in the alveolar parenchyma when mice struggle to recover from influenza infection. The receptor for IFN-γ on lung epithelium was essential for the formation of aberrant Krt5+ cells and fibrotic lung disease. The transcription factor Yes-associated protein 1 (YAP) was necessary for persistence of these Krt5+ cells, and IFN-γ activated YAP in lung epithelial cells via JAK, focal adhesion kinase (FAK), and Src kinases. These findings establish a targetable pathway underlying some of the pulmonary postacute sequelae of pneumonia.
Assuntos
Interferon gama , Proteínas de Sinalização YAP , Animais , Camundongos , Proteínas de Sinalização YAP/metabolismo , Interferon gama/metabolismo , Humanos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologiaRESUMO
BACKGROUND: The alveolar epithelium is protected by a heparan sulfate-rich, glycosaminoglycan layer called the epithelial glycocalyx. It is cleaved in patients with acute respiratory distress syndrome (ARDS) and in murine models of influenza A (IAV) infection, shedding fragments into the airspace from the cell surface. Glycocalyx shedding results in increased permeability of the alveolar-capillary barrier, amplifying acute lung injury. The mechanisms underlying alveolar epithelial glycocalyx shedding in IAV infection are unknown. We hypothesized that induction of host sheddases such as matrix metalloproteinases (MMPs) during IAV infection results in glycocalyx shedding and increased lung injury. MATERIALS AND METHODS: We measured glycocalyx shedding and lung injury during IAV infection with and without treatment with the pan-MMP inhibitor Ilomastat (ILO) and in an MMP-7 knock out (MMP-7KO) mouse. C57BL/6 or MMP-7KO male and female mice were given IAV A/PR/8/34 (H1N1) at 30,000 PFU/mouse or PBS intratracheally. For some experiments, C56BL/6 mice were infected in the presence of ILO (100mg/kg) or vehicle given daily by IP injection. Bronchoalveolar lavage (BAL) and lung tissue were collected on day 1, 3, and 7 for analysis of glycocalyx shedding (BAL Syndecan-1) and lung injury (histology, BAL protein, BAL cytokines, BAL immune cell infiltrates, BAL RAGE). Expression and localization of the sheddase MMP-7 and its inhibitor TIMP-1 was examined by RNAScope. For in vitro experiments, MLE-12 mouse lung epithelial cells were cultured and treated with active or heat-inactivated heparinase (2.5 U/mL) prior to infection with IAV (MOI 1) and viral load and MMP-7 and TIMP-1 expression analyzed. RESULTS: IAV infection caused shedding of the epithelial glycocalyx into the BAL. Inhibition of MMPs with ILO reduced glycocalyx shedding by 36% (p = 0.0051) and reduced lung epithelial injury by 40% (p = 0.0404). ILO also reduced viral load by 68% (p = 0.027), despite having no significant effect on lung cytokine production. Both MMP-7 and its inhibitor TIMP-1 were upregulated in IAV infected mice: MMP-7 colocalized with IAV, while TIMP-1 was limited to cells adjacent to infection. However, MMP-7KO mice had similar glycocalyx shedding, epithelial injury, and viral load compared to WT littermates, suggesting redundancy in MMP sheddase function in the lung. In vitro, heparinase treatment before infection led to a 52% increase in viral load (p = 0.0038) without altering MMP-7 or TIMP-1 protein levels. CONCLUSIONS: Glycocalyx shedding and MMPs play key roles in IAV-induced epithelial injury, with significant impact on IAV viral load. Further studies are needed to understand which specific MMPs regulate lung epithelial glycocalyx shedding.
Assuntos
Glicocálix , Metaloproteinase 7 da Matriz , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae , Animais , Glicocálix/metabolismo , Camundongos , Feminino , Masculino , Metaloproteinase 7 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/genética , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/patologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Camundongos Knockout , Alvéolos Pulmonares/virologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Ácidos Hidroxâmicos/farmacologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Metaloproteinases da Matriz/metabolismo , IndóisRESUMO
The lymphatic system consists of a vessel network lined by specialized lymphatic endothelial cells (LECs) that are responsible for tissue fluid homeostasis and immune cell trafficking. The mechanisms for organ-specific LEC responses to environmental cues are not well understood. We found robust lymphangiogenesis during influenza A virus infection in the adult mouse lung. We show that the number of LECs increases twofold at 7 days post-influenza infection (dpi) and threefold at 21 dpi, and that lymphangiogenesis is preceded by lymphatic dilation. We also show that the expanded lymphatic network enhances fluid drainage to mediastinal lymph nodes. Using EdU labeling, we found that a significantly higher number of pulmonary LECs are proliferating at 7 dpi compared to LECs in homeostatic conditions. Lineage tracing during influenza indicates that new pulmonary LECs are derived from preexisting LECs rather than non-LEC progenitors. Lastly, using a conditional LEC-specific YAP/TAZ knockout model, we established that lymphangiogenesis, fluid transport and the immune response to influenza are independent of YAP/TAZ activity in LECs. These findings were unexpected, as they indicate that YAP/TAZ signaling is not crucial for these processes.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Células Endoteliais , Pulmão , Linfangiogênese , Infecções por Orthomyxoviridae , Proteínas de Sinalização YAP , Animais , Proteínas de Sinalização YAP/metabolismo , Células Endoteliais/metabolismo , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Pulmão/metabolismo , Pulmão/patologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/patologia , Vírus da Influenza A/fisiologia , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Camundongos Knockout , Transdução de Sinais , Proliferação de Células , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Camundongos Endogâmicos C57BL , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Increased circulating tissue inhibitor of metalloproteinases-1 (TIMP-1) levels have been observed in patients with acute lung injury (ALI). However, the sex-specific regulation of TIMP-1 and the underlying molecular mechanisms have not been well elucidated. In this study, we found that plasma TIMP-1 levels were significantly higher in COVID-19 and H1N1 patients compared with those in healthy subjects (n = 25). TIMP-1 concentrations were significantly different between males and females in each disease group. Among female but not male patients, TIMP-1 levels significantly correlated with the PaO2/FiO2 ratio and hospital length of stay. Using the mouse model of ALI induced by the H1N1 virus, we found that TIMP-1 is strikingly induced in PDGFRα-positive cells in the murine lungs. Moreover, female mice showed a higher Timp-1 expression in the lungs on day 3 postinfection. Mechanistically, we observed that estrogen can upregulate TIMP-1 expression in lung fibroblasts, not epithelial cells. In addition, overexpression of estrogen receptor α (ERα) increased the TIMP-1 promoter activity. In summary, TIMP-1 is an estrogen-responsive gene, and its promoter activity is regulated by ERα. Circulating TIMP-1 may serve as a sex-specific marker, reflecting the severity and worst outcomes in female patients with SARS-CoV2- and IAV-related ALI.
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Lesão Pulmonar Aguda , Biomarcadores , COVID-19 , Receptor alfa de Estrogênio , Inibidor Tecidual de Metaloproteinase-1 , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/sangue , Animais , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/sangue , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Feminino , Masculino , Humanos , Camundongos , COVID-19/metabolismo , COVID-19/genética , COVID-19/sangue , Receptor alfa de Estrogênio/metabolismo , Receptor alfa de Estrogênio/genética , Biomarcadores/sangue , Biomarcadores/metabolismo , Estrogênios/sangue , Pessoa de Meia-Idade , Vírus da Influenza A Subtipo H1N1 , Pulmão/metabolismo , SARS-CoV-2 , Adulto , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Fatores Sexuais , Caracteres Sexuais , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/genéticaRESUMO
Influenza A virus (IAV) infection while primarily affecting the lungs, is often associated with cardiovascular complications. However, the mechanisms underlying this association are not fully understood. Here, we investigated the potential role of FBXL19, a member of the Skp1-Cullin-1-F-box family of E3 ubiquitin ligase, in IAV-induced cardiac inflammation. We demonstrated that FBXL19 overexpression in endothelial cells (ECs) reduced viral titers and IAV matrix protein 1 (M1) levels while increasing antiviral gene expression, including interferon (IFN)-α, -ß, and -γ and RANTES (regulated on activation normal T cell expressed and secreted) in the cardiac tissue of IAV-infected mice. Moreover, EC-specific overexpression of FBXL19 attenuated the IAV infection-reduced interferon regulatory factor 3 (IRF3) level without altering its mRNA level and suppressed cardiac inflammation. Furthermore, IAV infection triggered cellular senescence programs in the heart as indicated by the upregulation of p16 and p21 mRNA levels and the downregulation of lamin-B1 levels, which were partially reversed by FBXL19 overexpression in ECs. Our findings indicate that EC-specific overexpression of FBXL19 protects against IAV-induced cardiac damage by enhancing interferon-mediated antiviral signaling, reducing cardiac inflammation, and suppressing cellular senescence programs.NEW & NOTEWORTHY Our study reveals a novel facet of IAV infection, demonstrating that it can trigger cellular senescence within the heart. Intriguingly, upregulation of endothelial FBXL19 promotes host innate immunity, reduces cardiac senescence, and diminishes inflammation. These findings highlight the therapeutic potential of targeting FBXL19 to mitigate IAV-induced cardiovascular complications.
Assuntos
Senescência Celular , Células Endoteliais , Fator Regulador 3 de Interferon , Infecções por Orthomyxoviridae , Animais , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/imunologia , Células Endoteliais/virologia , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , Camundongos Endogâmicos C57BL , Camundongos , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Humanos , Vírus da Influenza A/patogenicidade , Miocárdio/metabolismo , Miocárdio/imunologia , Miocárdio/patologia , Modelos Animais de Doenças , Transdução de Sinais , Interferons/metabolismo , Interferons/genética , Masculino , Quimiocina CCL5RESUMO
Obesity is a risk factor for increased morbidity and mortality in viral respiratory infection. Mucociliary clearance (MCC) in the airway is the primary host defense against viral infections. However, the impact of obesity on MCC is unclear, prompting this study. Using murine tracheal tissue culture and in vitro influenza A virus (IAV) infection models, we analyzed cilia-driven flow and ciliary beat frequency (CBF) in the airway epithelium to evaluate MCC. Short-term IAV infection increased cilia-driven flow and CBF in control mice, but not in high-fat diet-induced obese mice. Basal cilia-driven flow and CBF were also lower in obese mice than in control mice. Mechanistically, the increase of extracellular adenosine triphosphate (ATP) release during IAV infection, which was observed in the control mice, was abolished in the obese mice; however, the addition of ATP increased cilia-driven flow and CBF both in control and obese mice to a similar extent. In addition, RNA sequencing and reverse transcription-polymerase chain reaction revealed the downregulation of several cilia-related genes, including Dnah1, Dnal1, Armc4, and Ttc12 (the dynein-related genes); Ulk4 (the polychaete differentiation gene); Cep164 (the ciliogenesis and intraflagellar transport gene); Rsph4a, Cfap206, and Ppil6 (the radial spoke structure and assembly gene); and Drc3(the nexin-dynein regulatory complex genes) in obese murine tracheal tissues compared with their control levels. In conclusion, our studies demonstrate that obesity attenuates MCC under basal conditions and during IAV infection by downregulating the expression of cilia-related genes and suppressing the release of extracellular ATP, thereby increasing the susceptibility and severity of IAV infection.NEW & NOTEWORTHY Our study shows that obesity impairs airway mucociliary clearance (MCC), an essential physical innate defense mechanism for viral infection. Mechanically, this is likely due to the obesity-induced downregulation of cilia-related genes and attenuation of extracellular ATP release. This study provides novel insights into the mechanisms driving the higher susceptibility and severity of viral respiratory infections in individuals with obesity.
Assuntos
Cílios , Depuração Mucociliar , Obesidade , Mucosa Respiratória , Animais , Cílios/metabolismo , Cílios/patologia , Obesidade/metabolismo , Obesidade/patologia , Obesidade/fisiopatologia , Obesidade/complicações , Camundongos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Camundongos Endogâmicos C57BL , Trifosfato de Adenosina/metabolismo , Masculino , Traqueia/metabolismo , Traqueia/virologia , Traqueia/patologia , Vírus da Influenza A , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/metabolismo , Dieta Hiperlipídica/efeitos adversosRESUMO
Introduction: Introduction: The influenza virus primarily targets the respiratory tract, yet both the respiratory and intestinal systems suffer damage during infection. The connection between lung and intestinal damage remains unclear. Methods: Our experiment employs 16S rRNA technology and Liquid Chromatography-Mass Spectrometry (LC-MS) to detect the impact of influenza virus infection on the fecal content and metabolites in mice. Additionally, it investigates the effect of influenza virus infection on intestinal damage and its underlying mechanisms through HE staining, Western blot, Q-PCR, and flow cytometry. Results: Our study found that influenza virus infection caused significant damage to both the lungs and intestines, with the virus detected exclusively in the lungs. Antibiotic treatment worsened the severity of lung and intestinal damage. Moreover, mRNA levels of Toll-like receptor 7 (TLR7) and Interferon-b (IFN-b) significantly increased in the lungs post-infection. Analysis of intestinal microbiota revealed notable shifts in composition after influenza infection, including increased Enterobacteriaceae and decreased Lactobacillaceae. Conversely, antibiotic treatment reduced microbial diversity, notably affecting Firmicutes, Proteobacteria, and Bacteroidetes. Metabolomics showed altered amino acid metabolism pathways due to influenza infection and antibiotics. Abnormal expression of indoleamine 2,3-dioxygenase 1 (IDO1) in the colon disrupted the balance between helper T17 cells (Th17) and regulatory T cells (Treg cells) in the intestine. Mice infected with the influenza virus and supplemented with tryptophan and Lactobacillus showed reduced lung and intestinal damage, decreased Enterobacteriaceae levels in the intestine, and decreased IDO1 activity. Discussion: Overall, influenza infection caused damage to lung and intestinal tissues, disrupted intestinal microbiota and metabolites, and affected Th17/Treg balance. Antibiotic treatment exacerbated these effects. Supplementation with tryptophan and Lactobacillus improved lung and intestinal health, highlighting a new understanding of the lung-intestine connection in influenza-induced intestinal disease.
Assuntos
Modelos Animais de Doenças , Microbioma Gastrointestinal , Pulmão , Infecções por Orthomyxoviridae , Animais , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Camundongos , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/metabolismo , Pulmão/virologia , Receptor 7 Toll-Like/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos Endogâmicos C57BL , Intestinos/imunologia , Intestinos/microbiologia , Intestinos/virologia , Feminino , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Transdução de Sinais , RNA Ribossômico 16S/genética , Glicoproteínas de MembranaRESUMO
BACKGROUND: Adenosine triphosphate (ATP) enhances neutrophil responses, but little is known about the role of ATP in influenza infections. METHODS: We used a mouse influenza model to study if ATP release is associated with neutrophil activation and disease progression. RESULTS: Influenza infection increased pulmonary ATP levels 5-fold and plasma ATP levels 3-fold vs healthy mice. Adding ATP at those concentrations to blood from healthy mice primed neutrophils and enhanced CD11b and CD63 expression, CD62L shedding, and reactive oxygen species production in response to formyl peptide receptor stimulation. Influenza infection also primed neutrophils in vivo, resulting in formyl peptide receptor-induced CD11b expression and CD62L shedding up to 3 times higher than that of uninfected mice. In infected mice, large numbers of neutrophils entered the lungs. These cells were significantly more activated than the peripheral neutrophils of infected mice and pulmonary neutrophils of healthy mice. Plasma ATP levels of infected mice and influenza disease progression corresponded with the numbers and activation level of their pulmonary neutrophils. CONCLUSIONS: Findings suggest that ATP release from the lungs of infected mice promotes influenza disease progression by priming peripheral neutrophils, which become strongly activated and cause pulmonary tissue damage after their recruitment to the lungs.
Assuntos
Trifosfato de Adenosina , Progressão da Doença , Pulmão , Ativação de Neutrófilo , Neutrófilos , Infecções por Orthomyxoviridae , Animais , Trifosfato de Adenosina/metabolismo , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/metabolismo , Camundongos , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismoRESUMO
Mitochondria react to infection with sub-lethal signals in the apoptosis pathway. Mitochondrial signals can be inflammatory but mechanisms are only partially understood. We show that activation of the caspase-activated DNase (CAD) mediates mitochondrial pro-inflammatory functions and substantially contributes to host defense against viral infection. In cells lacking CAD, the pro-inflammatory activity of sub-lethal signals was reduced. Experimental activation of CAD caused transient DNA-damage and a pronounced DNA damage response, involving major kinase signaling pathways, NF-κB and cGAS/STING, driving the production of interferon, cytokines/chemokines and attracting neutrophils. The transcriptional response to CAD-activation was reminiscent of the reaction to microbial infection. CAD-deficient cells had a diminished response to viral infection. Influenza virus infected CAD-deficient mice displayed reduced inflammation in lung tissue, higher viral titers and increased weight loss. Thus, CAD links the mitochondrial apoptosis system and cell death caspases to host defense. CAD-driven DNA damage is a physiological element of the inflammatory response to infection.
Assuntos
Dano ao DNA , Inflamação , Mitocôndrias , Animais , Humanos , Camundongos , Apoptose , Desoxirribonucleases/metabolismo , Desoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/deficiência , Inflamação/patologia , Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Nucleotidiltransferases , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/metabolismo , Transdução de SinaisRESUMO
Influenza A virus (IAV) infection during pregnancy can increase the risk for neurodevelopmental disorders in the offspring, however, the underlying neurobiological mechanisms are largely unknown. To recapitulate viral infection, preclinical studies have traditionally focused on using synthetic viral mimetics, rather than live IAV, to examine consequences of maternal immune activation (MIA)-dependent processes on offspring. In contrast, few studies have used live IAV to assess effects on global gene expression, and none to date have addressed whether moderate IAV, mimicking seasonal influenza disease, alters normal gene expression trajectories in different brain regions across different stages of development. Herein, we show that moderate IAV infection during pregnancy, which causes mild maternal disease and no overt foetal complications in utero, induces lasting effects on the offspring into adulthood. We observed behavioural changes in adult offspring, including disrupted prepulse inhibition, dopaminergic hyper-responsiveness, and spatial recognition memory deficits. Gene profiling in the offspring brain from neonate to adolescence revealed persistent alterations to normal gene expression trajectories in the prefronal cortex, hippocampus, hypothalamus and cerebellum. Alterations were found in genes involved in inflammation and neurogenesis, which were predominately dysregulated in neonatal and early adolescent offspring. Notably, late adolescent offspring born from IAV infected mice displayed altered microglial morphology in the hippocampus. In conclusion, we show that moderate IAV during pregnancy perturbs neurodevelopmental trajectories in the offspring, including alterations in the neuroinflammatory gene expression profile and microglial number and morphology in the hippocampus, resulting in behavioural changes in adult offspring. Such early perturbations may underlie the vulnerability in human offspring for the later development of neurodevelopmental disorders, including schizophrenia. Our work highlights the importance of using live IAV in developing novel preclinical models that better recapitulate the real-world impact of inflammatory insults during pregnancy on offspring neurodevelopmental trajectories and disease susceptibility later in life.
Assuntos
Encéfalo , Vírus da Influenza A , Infecções por Orthomyxoviridae , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Gravidez , Camundongos , Encéfalo/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Complicações Infecciosas na Gravidez/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Hipocampo/metabolismo , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/genética , Expressão Gênica , Modelos Animais de DoençasRESUMO
Influenza virus infection is initiated by the attachment of the viral haemagglutinin (HA) protein to sialic acid receptors on the host cell surface. Most virus particles enter cells through clathrin-mediated endocytosis (CME). However, it is unclear how viral binding signals are transmitted through the plasma membrane triggering CME. Here we found that metabotropic glutamate receptor subtype 2 (mGluR2) and potassium calcium-activated channel subfamily M alpha 1 (KCa1.1) are involved in the initiation and completion of CME of influenza virus using an siRNA screen approach. Influenza virus HA directly interacted with mGluR2 and used it as an endocytic receptor to initiate CME. mGluR2 interacted and activated KCa1.1, leading to polymerization of F-actin, maturation of clathrin-coated pits and completion of the CME of influenza virus. Importantly, mGluR2-knockout mice were significantly more resistant to different influenza subtypes than the wild type. Therefore, blocking HA and mGluR2 interaction could be a promising host-directed antiviral strategy.
Assuntos
Endocitose , Camundongos Knockout , Receptores de Glutamato Metabotrópico , Animais , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Glutamato Metabotrópico/genética , Camundongos , Humanos , Internalização do Vírus , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Clatrina/metabolismo , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/metabolismo , Células HEK293 , Actinas/metabolismo , Cães , Células Madin Darby de Rim Canino , Receptores Virais/metabolismo , Receptores Virais/genética , Influenza Humana/virologia , Influenza Humana/metabolismo , Orthomyxoviridae/fisiologia , Orthomyxoviridae/genética , Orthomyxoviridae/metabolismoRESUMO
Influenza is a significant public health and economic threat around the world. Epidemiological studies have demonstrated a close association between influenza pandemics and cardiovascular mortality. Moreover, it has been shown that there is a decrease in cardiovascular mortality in high-risk patients following vaccination with the influenza vaccine. Here, we have investigated the role of anti-viral STAT1 signaling in influenza-induced myocarditis. Wild-type mice (C57BL/6) were infected with either influenza A/PR/8/34 or control, and cellular response and gene expression analysis from the heart samples were assessed 7 days later. The expression of interferon response genes STAT1, STAT2, Mx1, OASL2, ISG15, chemokines CCL2, CCL3, CXCL9 and CXCL10, and the frequency of neutrophils (CD45+CD11b+Ly6G+) and CD4+ T cells (CD45+CD4+) were all significantly increased in influenza-infected mice when compared to vehicle controls. These data suggest that influenza infection induces interferons, inflammatory chemokines, and cellular recruitment during influenza infection. We further investigated the role of STAT1 in influenza-induced myocarditis. The frequency of neutrophils and the levels of lipocalin 2 were significantly increased in STAT1-/- mice when compared to WT controls. Finally, we investigated the role of Lcn2 in viral-induced myocarditis. We found that in the absence of Lcn2, there was preserved cardiac function in Lcn2-/- mice when compared to WT controls. These data suggest that the absence of Lcn2 is cardioprotective during viral-induced myocarditis.
Assuntos
Lipocalina-2 , Camundongos Endogâmicos C57BL , Miocardite , Infecções por Orthomyxoviridae , Fator de Transcrição STAT1 , Animais , Camundongos , Lipocalina-2/metabolismo , Lipocalina-2/genética , Camundongos Knockout , Miocardite/virologia , Miocardite/metabolismo , Miocardite/etiologia , Neutrófilos/metabolismo , Neutrófilos/imunologia , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT1/genéticaRESUMO
Respiratory viral infection increases host susceptibility to secondary bacterial infections, yet the precise dynamics within airway epithelia remain elusive. Here, we elucidate the pivotal role of CD47 in the airway epithelium during bacterial super-infection. We demonstrated that upon influenza virus infection, CD47 expression was upregulated and localized on the apical surface of ciliated cells within primary human nasal or bronchial epithelial cells. This induced CD47 exposure provided attachment sites for Staphylococcus aureus, thereby compromising the epithelial barrier integrity. Through bacterial adhesion assays and in vitro pull-down assays, we identified fibronectin-binding proteins (FnBP) of S. aureus as a key component that binds to CD47. Furthermore, we found that ciliated cell-specific CD47 deficiency or neutralizing antibody-mediated CD47 inactivation enhanced in vivo survival rates. These findings suggest that interfering with the interaction between airway epithelial CD47 and pathogenic bacterial FnBP holds promise for alleviating the adverse effects of super-infection.
Assuntos
Antígeno CD47 , Células Epiteliais , Infecções Estafilocócicas , Staphylococcus aureus , Superinfecção , Antígeno CD47/metabolismo , Antígeno CD47/genética , Humanos , Animais , Superinfecção/microbiologia , Camundongos , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/virologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/microbiologia , Influenza Humana/metabolismo , Influenza Humana/imunologia , Influenza Humana/virologia , Aderência Bacteriana , Mucosa Respiratória/metabolismo , Mucosa Respiratória/microbiologia , Mucosa Respiratória/virologia , Camundongos Endogâmicos C57BL , Brônquios/metabolismo , Brônquios/citologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Camundongos Knockout , Vírus da Influenza A Subtipo H1N1RESUMO
BACKGROUND: Influenza A virus (IAV) infection is a significant risk factor for respiratory diseases, but the host defense mechanisms against IAV remain to be defined. Immune regulators such as surfactant protein A (SP-A) and Toll-interacting protein (Tollip) have been shown to be involved in IAV infection, but whether SP-A and Tollip cooperate in more effective host defense against IAV infection has not been investigated. METHODS: Wild-type (WT), Tollip knockout (KO), SP-A KO, and Tollip/SP-A double KO (dKO) mice were infected with IAV for four days. Lung macrophages were isolated for bulk RNA sequencing. Precision-cut lung slices (PCLS) from WT and dKO mice were pre-treated with SP-A and then infected with IAV for 48 h. RESULTS: Viral load was significantly increased in bronchoalveolar lavage (BAL) fluid of dKO mice compared to all other strains of mice. dKO mice had significantly less recruitment of neutrophils into the lung compared to Tollip KO mice. SP-A treatment of PCLS enhanced expression of TNF and reduced viral load in dKO mouse lung tissue. Pathway analysis of bulk RNA sequencing data suggests that macrophages from IAV-infected dKO mice reduced expression of genes involved in neutrophil recruitment, IL-17 signaling, and Toll-like receptor signaling. CONCLUSIONS: Our data suggests that both Tollip and SP-A are essential for the lung to exert more effective innate defense against IAV infection.
Assuntos
Vírus da Influenza A , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae , Proteína A Associada a Surfactante Pulmonar , Animais , Proteína A Associada a Surfactante Pulmonar/metabolismo , Proteína A Associada a Surfactante Pulmonar/genética , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/metabolismo , Vírus da Influenza A/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologiaRESUMO
The most prevalent glycoprotein on the influenza virus envelope is called hemagglutinin (HA), yet little is known about its involvement in the pathophysiology and etiology of severe influenza pneumonia. Here, after stimulating human bronchial epithelial cells (16-HBE) and mice with HA of H1N1 for 12 h, we investigated the proliferation, migration, inflammatory cytokines expression, and apoptosis in 16-HBE and the pathological damage in mouse lung tissue. The expression of inflammatory cytokines plasminogen activator inhibitor 1(PAI-1), urokinase-type (uPA) and tissue-type (tPA) plasminogen activators, and apoptosis were all enhanced by HA, which also prevented the proliferation and migration of bronchial epithelial cells. HA enhanced up-regulated PAI-1, uPA, and tPA protein expression within mouse lung tissue and caused lung injury. In conclusion, HA alone, but not the whole H1N1 virus, induces lung tissue injury by inhibiting cell proliferation and migration, while promoting the expression of inflammatory cytokines and apoptosis.
Assuntos
Apoptose , Proliferação de Células , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza A Subtipo H1N1 , Animais , Humanos , Camundongos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Movimento Celular , Citocinas/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Pulmão/metabolismo , Pulmão/virologia , Pulmão/patologia , Linhagem Celular , Pneumonia Viral/virologia , Pneumonia Viral/metabolismo , Pneumonia Viral/patologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Pneumonia/metabolismo , Pneumonia/virologiaRESUMO
Children are susceptible to influenza infections and can experience severe disease presentation due to a lack of or limited pre-existing immunity. Despite the disproportionate impact influenza has on this population, there is a lack of focus on pediatric influenza research, particularly when it comes to identifying the pathogenesis of long-term outcomes that persist beyond the point of viral clearance. In this study, juvenile outbred male and female mice were infected with influenza and analyzed following viral clearance to determine how sex impacts the persistent inflammatory responses to influenza. It was found that females maintained a broader cytokine response in the lung following clearance of influenza, with innate, type I and type II cytokine signatures in almost all mice. Males, on the other hand, had higher levels of IL-6 and other macrophage-related cytokines, but no evidence of a type I or type II response. The immune landscape was similar in the lungs between males and females postinfection, but males had a higher regulatory T cell to TH1 ratio compared with female mice. Cytokine production positively correlated with the frequency of TH1 cells and exudate macrophages, as well as the number of cells in the bronchoalveolar lavage fluid. Furthermore, female lungs were enriched for metabolites involved in the glycolytic pathway, suggesting glycolysis is higher in female lungs compared with males after viral clearance. These data suggest juvenile female mice have persistent and excessive lung inflammation beyond the point of viral clearance, whereas juvenile males had a more immunosuppressive phenotype.NEW & NOTEWORTHY This study identifies sex-based differences in persistent lung inflammation following influenza infection in an outbred, juvenile animal model of pediatric infection. These findings indicate the importance of considering sex and age as variable in infectious disease research.
Assuntos
Citocinas , Infecções por Orthomyxoviridae , Pneumonia , Caracteres Sexuais , Animais , Feminino , Masculino , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/metabolismo , Camundongos , Citocinas/metabolismo , Pneumonia/virologia , Pneumonia/patologia , Pneumonia/imunologia , Pneumonia/metabolismo , Pulmão/virologia , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Macrófagos/virologia , Fatores SexuaisRESUMO
We have recently reported that transcription factor Runx3 is required for pulmonary generation of CD8+ cytotoxic T lymphocytes (CTLs) that play a crucial role in the clearance of influenza A virus (IAV). To understand the underlying mechanisms, we determined the effects of Runx3 knockout (KO) on CD8+ T cell local expansion and phenotypes using an inducible general Runx3 KO mouse model. We found that in contrast to the lungs, Runx3 general KO promoted enlargement of lung-draining mediastinal lymph node (mLN) and enhanced CD8+ and CD4+ T cell expansion during H1N1 IAV infection. We further found that Runx3 deficiency greatly inhibited core 2 O-glycosylation of selectin ligand CD43 on activated CD8+ T cells but minimally affected the cell surface expression of CD43, activation markers (CD44 and CD69) and cell adhesion molecules (CD11a and CD54). Runx3 KO had a minor effect on lung effector CD8+ T cell death by IAV infection. Our findings indicate that Runx3 differently regulates CD8+ T cell expansion in mLNs and lungs by H1N1 IAV infection. Runx3 is required for CD43 core 2 O-glycosylation on activated CD8+ T cells, and the involved Runx3 signal pathway may mediate CD8+ T cell phenotype for pulmonary generation of CTLs.
Assuntos
Linfócitos T CD8-Positivos , Subunidade alfa 3 de Fator de Ligação ao Core , Vírus da Influenza A Subtipo H1N1 , Infecções por Orthomyxoviridae , Animais , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Glicosilação , Vírus da Influenza A Subtipo H1N1/imunologia , Leucossialina/metabolismo , Pulmão/virologia , Pulmão/metabolismo , Pulmão/imunologia , Pulmão/patologia , Linfonodos/metabolismo , Linfonodos/imunologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologiaRESUMO
BACKGROUND: Influenza A viruses (IAV) are extremely common respiratory viruses for the acute exacerbation of chronic obstructive pulmonary disease (AECOPD), in which IAV infection may further evoke abnormal macrophage polarization, amplify cytokine storms. Melatonin exerts potential effects of anti-inflammation and anti-IAV infection, while its effects on IAV infection-induced AECOPD are poorly understood. METHODS: COPD mice models were established through cigarette smoke exposure for consecutive 24 weeks, evaluated by the detection of lung function. AECOPD mice models were established through the intratracheal atomization of influenza A/H3N2 stocks in COPD mice, and were injected intraperitoneally with melatonin (Mel). Then, The polarization of alveolar macrophages (AMs) was assayed by flow cytometry of bronchoalveolar lavage (BAL) cells. In vitro, the effects of melatonin on macrophage polarization were analyzed in IAV-infected Cigarette smoking extract (CSE)-stimulated Raw264.7 macrophages. Moreover, the roles of the melatonin receptors (MTs) in regulating macrophage polarization and apoptosis were determined using MTs antagonist luzindole. RESULTS: The present results demonstrated that IAV/H3N2 infection deteriorated lung function (reduced FEV20,50/FVC), exacerbated lung damages in COPD mice with higher dual polarization of AMs. Melatonin therapy improved airflow limitation and lung damages of AECOPD mice by decreasing IAV nucleoprotein (IAV-NP) protein levels and the M1 polarization of pulmonary macrophages. Furthermore, in CSE-stimulated Raw264.7 cells, IAV infection further promoted the dual polarization of macrophages accompanied with decreased MT1 expression. Melatonin decreased STAT1 phosphorylation, the levels of M1 markers and IAV-NP via MTs reflected by the addition of luzindole. Recombinant IL-1ß attenuated the inhibitory effects of melatonin on IAV infection and STAT1-driven M1 polarization, while its converting enzyme inhibitor VX765 potentiated the inhibitory effects of melatonin on them. Moreover, melatonin inhibited IAV infection-induced apoptosis by suppressing IL-1ß/STAT1 signaling via MTs. CONCLUSIONS: These findings suggested that melatonin inhibited IAV infection, improved lung function and lung damages of AECOPD via suppressing IL-1ß/STAT1-driven macrophage M1 polarization and apoptosis in a MTs-dependent manner. Melatonin may be considered as a potential therapeutic agent for influenza virus infection-induced AECOPD.
Assuntos
Apoptose , Vírus da Influenza A Subtipo H3N2 , Melatonina , Doença Pulmonar Obstrutiva Crônica , Animais , Melatonina/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/virologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Camundongos , Apoptose/efeitos dos fármacos , Células RAW 264.7 , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/imunologia , Camundongos Endogâmicos C57BL , Masculino , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Progressão da Doença , Polaridade Celular/efeitos dos fármacos , Modelos Animais de Doenças , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologiaRESUMO
Uncontrolled inflammation contributes significantly to the mortality in acute respiratory infections. Our previous research has demonstrated that maize bran feruloylated oligosaccharides (FOs) possess notable anti-inflammatory properties linked to the NF-kB pathway regulation. In this study, we clarified that the oral administration of FOs moderately inhibited H1N1 virus infection and reduced lung inflammation in influenza-infected mice by decreasing a wide spectrum of cytokines (IFN-α, IFN-ß, IL-6, IL-10, and IL-23) in the lungs. The mechanism involves FOs suppressing the transduction of the RIG-I/MAVS/TRAF3 signaling pathway, subsequently lowering the expression of NF-κB. In silico analysis suggests that FOs have a greater binding affinity for the RIG-I/MAVS signaling complex. This indicates that FOs have potential as promising targets for immune modulation. Moreover, in MAVS knockout mice, we confirmed that the anti-inflammatory function of FOs against influenza depends on MAVS. Comprehensive analysis using 16S rRNA gene sequencing and metabolite profiling techniques showed that FOs have the potential to restore immunity by modulating the gut microbiota. In conclusion, our study demonstrates that FOs are effective anti-inflammatory phytochemicals in inhibiting lung inflammation caused by influenza. This suggests that FOs could serve as a potential nutritional strategy for preventing the H1N1 virus infection and associated lung inflammation.
Assuntos
Proteína DEAD-box 58 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Camundongos Knockout , Oligossacarídeos , Infecções por Orthomyxoviridae , Transdução de Sinais , Fator 3 Associado a Receptor de TNF , Animais , Camundongos , Oligossacarídeos/administração & dosagem , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/metabolismo , Vírus da Influenza A Subtipo H1N1/imunologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/metabolismo , Fator 3 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/metabolismo , Fator 3 Associado a Receptor de TNF/imunologia , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/metabolismo , Proteína DEAD-box 58/imunologia , Pneumonia/imunologia , Pneumonia/prevenção & controle , Pneumonia/metabolismo , Pneumonia/virologia , Camundongos Endogâmicos C57BL , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/virologia , Citocinas/metabolismo , Citocinas/imunologia , Citocinas/genética , Feminino , NF-kappa B/imunologia , NF-kappa B/genética , NF-kappa B/metabolismo , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologiaRESUMO
Protein arginine methyltransferases (PRMTs) modify diverse protein targets and regulate numerous cellular processes; yet, their contributions to individual effector T cell responses during infections are incompletely understood. In this study, we identify PRMT5 as a critical regulator of CD4+ T follicular helper cell (Tfh) responses during influenza virus infection in mice. Conditional PRMT5 deletion in murine T cells results in an almost complete ablation of both Tfh and T follicular regulatory populations and, consequently, reduced B cell activation and influenza-specific Ab production. Supporting a potential mechanism, we observe elevated surface expression of IL-2Rα on non-T regulatory effector PRMT5-deficient T cells. Notably, IL-2 signaling is known to negatively impact Tfh differentiation. Collectively, our findings identify PRMT5 as a prominent regulator of Tfh programming, with potential causal links to IL-2 signaling.