RESUMO
SARS-CoV-2 infection can cause persistent respiratory sequelae. However, the underlying mechanisms remain unclear. Here we report that sub-lethally infected K18-human ACE2 mice show patchy pneumonia associated with histiocytic inflammation and collagen deposition at 21 and 45 days post infection (DPI). Transcriptomic analyses revealed that compared to influenza-infected mice, SARS-CoV-2-infected mice had reduced interferon-gamma/alpha responses at 4 DPI and failed to induce keratin 5 (Krt5) at 6 DPI in lung, a marker of nascent pulmonary progenitor cells. Histologically, influenza- but not SARS-CoV-2-infected mice showed extensive Krt5+ "pods" structure co-stained with stem cell markers Trp63/NGFR proliferated in the pulmonary consolidation area at both 7 and 14 DPI, with regression at 21 DPI. These Krt5+ "pods" structures were not observed in the lungs of SARS-CoV-2-infected humans or nonhuman primates. These results suggest that SARS-CoV-2 infection fails to induce nascent Krt5+ cell proliferation in consolidated regions, leading to incomplete repair of the injured lung.
Assuntos
COVID-19 , Influenza Humana , Camundongos , Humanos , Animais , SARS-CoV-2 , Pulmão , Perfilação da Expressão GênicaRESUMO
Coronavirus disease 2019 (COVID-19) is the latest respiratory pandemic caused by severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2). Although infection initiates in the proximal airways, severe and sometimes fatal symptoms of the disease are caused by infection of the alveolar type 2 (AT2) cells of the distal lung and associated inflammation. In this study, we develop primary human lung epithelial infection models to understand initial responses of proximal and distal lung epithelium to SARS-CoV-2 infection. Differentiated air-liquid interface (ALI) cultures of proximal airway epithelium and alveosphere cultures of distal lung AT2 cells are readily infected by SARS-CoV-2, leading to an epithelial cell-autonomous proinflammatory response with increased expression of interferon signaling genes. Studies to validate the efficacy of selected candidate COVID-19 drugs confirm that remdesivir strongly suppresses viral infection/replication. We provide a relevant platform for study of COVID-19 pathobiology and for rapid drug screening against SARS-CoV-2 and emergent respiratory pathogens.
Assuntos
Células Epiteliais Alveolares/virologia , Tratamento Farmacológico da COVID-19 , COVID-19/patologia , Pulmão/virologia , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Adulto , Idoso , Alanina/análogos & derivados , Alanina/farmacologia , Células Epiteliais Alveolares/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Pré-Escolar , Descoberta de Drogas/métodos , Células Epiteliais/virologia , Epitélio/metabolismo , Epitélio/virologia , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Cultura Primária de Células , Mucosa Respiratória/virologia , SARS-CoV-2/fisiologia , Replicação Viral/efeitos dos fármacosRESUMO
Secondary bacterial pneumonia is a significant complication of severe influenza infection and Staphylococcus aureus and Streptococcus pneumoniae are the primary pathogens of interest. IL-22 promotes S. aureus and S. pneumoniae host defense in the lung through epithelial integrity and induction of antimicrobial peptides and is inhibited by the soluble decoy receptor IL-22-binding protein (IL-22BP). Little is known about the effect of the IL-22/IL-22BP regulatory pathway on lung infection, and it has not been studied in the setting of super-infection. We exposed wild-type and IL-22BP-/- mice to influenza A/PR/8/34 for 6 days prior to infection with S. aureus (USA300) S. pneumoniae. Super-infected IL-22BP-/- mice had decreased bacterial burden and improved survival compared to controls. IL-22BP-/- mice exhibited decreased inflammation, increased lipocalin 2 expression, and deletion of IL-22BP was associated with preserved epithelial barrier function with evidence of improved tight junction stability. Human bronchial epithelial cells treated with IL-22Fc showed evidence of improved tight junctions compared to untreated cells. This study revealed that IL-22BP-/- mice are protected during influenza, bacterial super-infection, suggesting that IL-22BP has a pro-inflammatory role and impairs epithelial barrier function likely through interaction with IL-22.
Assuntos
Infecções Bacterianas/metabolismo , Infecções Bacterianas/microbiologia , Proteínas de Transporte/metabolismo , Interleucinas/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Superinfecção , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/patologia , Carga Bacteriana , Barreira Alveolocapilar/metabolismo , Barreira Alveolocapilar/patologia , Barreira Alveolocapilar/virologia , Proteínas de Transporte/genética , Modelos Animais de Doenças , Expressão Gênica , Interleucinas/genética , Contagem de Leucócitos , Masculino , Camundongos , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , Permeabilidade , Ligação Proteica , Staphylococcus aureus , Streptococcus pneumoniae , Junções Íntimas , Interleucina 22RESUMO
Seasonal and pandemic influenza is a cause of morbidity and mortality worldwide. Most people infected with influenza virus display mild-to-moderate disease phenotypes and recover within a few weeks. Influenza is known to cause persistent alveolitis in animal models; however, little is known about the molecular pathways involved in this phenotype. We challenged C57BL/6 mice with influenza A/PR/8/34 and examined lung pathologic processes and inflammation, as well as transcriptomic and epigenetic changes at 21 to 60 days after infection. Influenza induced persistent parenchymal lung inflammation, alveolar epithelial metaplasia, and epithelial endoplasmic reticulum stress that were evident after the clearance of virus and resolution of morbidity. Influenza infection induced robust changes in the lung transcriptome, including a significant impact on inflammatory and extracellular matrix protein expression. Despite the robust changes in lung gene expression, preceding influenza (21 days) did not exacerbate secondary Staphylococcus aureus infection. Finally, we examined the impact of influenza on miRNA expression in the lung and found an increase in miR-155. miR-155 knockout mice recovered from influenza infection faster than controls and had decreased lung inflammation and endoplasmic reticulum stress. These data illuminate the dynamic molecular changes in the lung in the weeks after influenza infection and characterize the repair process, identifying a novel role for miR-155.
Assuntos
Epigênese Genética , Pulmão/metabolismo , Pulmão/virologia , Infecções por Orthomyxoviridae/genética , Transcriptoma/genética , Cicatrização/genética , Animais , Progressão da Doença , Estresse do Retículo Endoplasmático/genética , Epitélio/patologia , Perfilação da Expressão Gênica , Inflamação/patologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Pneumonia/etiologia , Pneumonia/microbiologia , Linfócitos T/imunologia , Fatores de TempoRESUMO
Commensal microbiota are critical for the development of local immune responses. In this article, we show that gut microbiota can regulate CD4 T cell polarization during pulmonary fungal infections. Vancomycin drinking water significantly decreased lung Th17 cell numbers during acute infection, demonstrating that Gram-positive commensals contribute to systemic inflammation. We next tested a role for RegIIIγ, an IL-22-inducible antimicrobial protein with specificity for Gram-positive bacteria. Following infection, increased accumulation of Th17 cells in the lungs of RegIIIγ(-/-) and Il22(-/-) mice was associated with intestinal segmented filamentous bacteria (SFB) colonization. Although gastrointestinal delivery of rRegIIIγ decreased lung inflammatory gene expression and protected Il22(-/-) mice from weight loss during infection, it had no direct effect on SFB colonization, fungal clearance, or lung Th17 immunity. We further show that vancomycin only decreased lung IL-17 production in mice colonized with SFB. To determine the link between gut microbiota and lung immunity, serum-transfer experiments revealed that IL-1R ligands increase the accumulation of lung Th17 cells. These data suggest that intestinal microbiota, including SFB, can regulate pulmonary adaptive immune responses.
Assuntos
Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Microbioma Gastrointestinal/imunologia , Bactérias Gram-Positivas/imunologia , Pulmão/imunologia , Células Th17/imunologia , Animais , Antibacterianos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Células Cultivadas , Imunidade/efeitos dos fármacos , Interleucinas/genética , Interleucinas/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas a Pancreatite , Proteínas/genética , Proteínas/metabolismo , Vancomicina/uso terapêutico , Interleucina 22RESUMO
Interleukin (IL)-22 is a member of the IL-10 family of cytokines that has been extensively studied since its discovery in 2000. This review article aims to describe the cellular sources and signaling pathways of this cytokine as well as the functions of IL-22 in the intestine. In addition, this article describes the roles of IL-22 in the pathogenesis of several gastrointestinal diseases, including inhibition of inflammation and barrier defense against pathogens within the intestine. Since many of the functions of IL-22 in the intestine are incompletely understood, this review is meant to assess our current understanding of the roles of IL-22 and provide new opportunities for inquiry to improve human intestinal health and disease.
RESUMO
OBJECTIVE: The most common etiology of acute pancreatitis results from the impaction of gallstones or sludge in the distal common bile duct (CBD). The result is pancreatic duct obstruction, diversion of bile into the pancreas, or cholestasis. In the current study, we examined whether combining both aspects, that is, infusion of the bile acid taurocholate (TC) followed by bile duct ligation (BDL), could yield a more severe form of pancreatitis that mimics biliary pancreatitis. METHODS: In mice, after laparotomy, the CBD was infused with either normal saline (NS) or TC. Subsequently, the CBD was ligated at the ampulla. RESULTS: Mice receiving TC infusion followed by BDL (TC + BDL) had higher mortality compared with animals receiving intraductal NS with BDL (NS + BDL). The TC + BDL arm developed more severe and diffuse pancreatic necrosis. In addition, serum amylase, IL-6, and bilirubin were significantly higher. However, pancreatic edema as well as lung and liver injury were unchanged between TC + BDL and NS + BDL. CONCLUSIONS: In summary, the combination of bile infusion into the pancreas followed by BDL causes a more severe, necrotizing pancreatitis. We believe that this novel model of pancreatitis is useful because it can be used in transgenic mice and recapitulates several aspects of biliary pancreatitis.
Assuntos
Colestase/complicações , Ducto Colédoco/cirurgia , Cálculos Biliares/induzido quimicamente , Pancreatite Necrosante Aguda/induzido quimicamente , Ácido Taurocólico , Amilases/sangue , Animais , Bilirrubina/sangue , Biomarcadores/sangue , Modelos Animais de Doenças , Interleucina-6/sangue , Ligadura , Masculino , Camundongos , Pâncreas/enzimologia , Pâncreas/patologia , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/patologia , Índice de Gravidade de Doença , Fatores de TempoRESUMO
Recent findings demonstrate that inhaled cigarette smoke, the predominant lung carcinogen, elicits a T helper 17 (Th17) inflammatory phenotype. Interleukin-17A (IL-17), the hallmark cytokine of Th17 inflammation, displays pro- and antitumorigenic properties in a manner that varies according to tumor type and assay system. To investigate the role of IL-17 in lung tumor growth, we used an autochthonous tumor model (K-Ras(LA1) mice) with lung delivery of a recombinant adenovirus that expresses IL-17A. Virus-mediated expression of IL-17A in K-Ras(LA1) mice at 8-10 wk of age doubled lung tumor growth in 3 wk relative to littermates that received a green fluorescent protein-expressing control adenovirus. IL-17 induced matrix metalloproteinase-9 (MMP-9) expression in vivo and in vitro. In accord with this finding, selective and specific inhibitors of MMP-9 repressed the increased motility and invasiveness of IL-17-treated lung tumor cells in culture. Knockdown or mutation of p53 promoted the motility of murine lung tumor cells and abrogated the promigratory role of IL-17. Coexpression of siRNA-resistant wild-type, but not mutant, human p53 rescued both IL-17-mediated migration and MMP-9 mRNA induction in p53 knockdown lung tumor cells. IL-17 increased MMP-9 mRNA stability by reducing interaction with the mRNA destabilizing serine/arginine-rich splicing factor 1 (SRSF1). Taken together, our results indicate that IL-17 stimulates lung tumor growth and regulates MMP-9 mRNA levels in a p53- and SRSF1-dependent manner.
Assuntos
Movimento Celular , Interleucina-17/biossíntese , Neoplasias Pulmonares/metabolismo , Animais , Estabilidade Enzimática/genética , Técnicas de Silenciamento de Genes , Humanos , Interleucina-17/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Fatores de Processamento de RNA , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/genética , Fatores de Processamento de Serina-Arginina , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genéticaRESUMO
The incidence of community-associated methicillin-resistant Staphylococcus aureus (MRSA) pneumonia in previously healthy individuals has increased in the past 5 years. Such infections are associated with bronchiectasis and high mortality rates, making them a significant public health concern. The mechanisms of host defense against this pathogen are not well characterized. However, patients diagnosed with MRSA, as opposed to methicillin-susceptible S. aureus (MSSA), are more likely to have abused alcohol in the past, and these patients are more likely to die from sepsis. In the United States, USA300 is the predominant strain that causes necrotizing pneumonia. To investigate whether acute ethanol exacerbates MRSA pneumonia, mice were intraperitoneally (i.p.) administered 2 or 4 g/kg of ethanol 30 min prior to oropharyngeal inoculation of 2 × 10(7) CFU of USA300. An increased pulmonary bacterial burden was observed in alcohol-intoxicated mice at 16 and 24 h and was associated with decreased levels of interleukin 6 (IL-6). IL-6 activates signal transducer and activator of transcription 3 (STAT3) as part of an acute-phase response of infection. Reg3γ is an antimicrobial C-type lectin that is induced by STAT3 signaling in response to Gram-positive bacteria. Previously, in situ hybridization studies showed that Reg3g is highly expressed in lung epithelium. In the present study, we found that acute ethanol exacerbated USA300 in a murine model of USA300 pneumonia. This was associated with reduced IL-6 expression in vivo as well as inhibition of IL-6 induction of STAT3 signaling and Reg3g expression in mouse lung epithelial (MLE12) cells in vitro. Furthermore, recombinant Reg3γ administration 4 h after MRSA infection in alcohol-intoxicated mice rescued USA300 clearance in vivo. Therefore, acute alcohol intoxication leads to decreased MRSA clearance in part by inhibiting IL-6/STAT3 induction of the antimicrobial protein Reg3γ in the pulmonary epithelium.
Assuntos
Intoxicação Alcoólica , Staphylococcus aureus Resistente à Meticilina , Pneumonia Estafilocócica , Proteínas/metabolismo , Doença Aguda , Intoxicação Alcoólica/imunologia , Intoxicação Alcoólica/microbiologia , Análise de Variância , Animais , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Etanol/farmacologia , Interleucina-6/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas a Pancreatite , Pneumonia Estafilocócica/imunologia , Pneumonia Estafilocócica/metabolismo , Pneumonia Estafilocócica/microbiologia , Mucosa Respiratória/citologia , Fator de Transcrição STAT3/fisiologia , Transdução de SinaisRESUMO
Mucosal vaccines are thought to confer superior protection against mucosal infectious diseases. In addition, mucosal routes of vaccine delivery preferentially induce the generation of T helper 17 (Th17) cells, which produce the cytokine IL-17. Th17 cells are critical in mediating vaccine-induced immunity against several mucosal infectious diseases. However, IL-17 is also a potent proinflammatory cytokine, and we recently showed that IL-17 mediates immunopathology and lung injury after influenza infection in mice. In the present study, we tested the hypothesis that mucosal pre-exposure to Th17-inducing adjuvants can promote disease exacerbation upon subsequent infection with influenza virus. Mice mucosally pre-exposed to Th17-inducing adjuvants, such as type II heat-labile enterotoxin or cholera toxin, resulted in increased morbidity and exacerbated lung inflammation upon subsequent infection with influenza virus. Furthermore, the increased morbidity was accompanied by increased expression of inflammatory chemokines and increased accumulation of neutrophils. Importantly, blockade of the IL-17 pathway in mice pre-exposed to Th17-inducing adjuvants resulted in attenuation of the inflammatory phenotype seen in influenza-infected mice. Our findings indicate that, before mucosal Th17-inducing adjuvants can be used in vaccine strategies, the short- and long-term detrimental effects of such adjuvants on disease exacerbation and lung injury in response to infections, such as influenza, should be carefully studied.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Infecções por Orthomyxoviridae/imunologia , Células Th17/imunologia , Animais , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Hibridização In Situ , Vírus da Influenza A , Vacinas contra Influenza/imunologia , Interleucina-17/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucosa/imunologia , Infecções por Orthomyxoviridae/patologia , Reação em Cadeia da PolimeraseRESUMO
OBJECTIVE: Chlamydia trachomatis infections are a significant cause of reproductive tract pathology. Protective and pathological immune mediators must be differentiated to design a safe and effective vaccine. METHODS: Wild-type mice and mice deficient in IL-22 and IL-23 were infected intravaginally with Chlamydia muridarum, and their course of infection and oviduct pathology were compared. Local genital tract and draining lymph node immune responses were also examined in IL-23-deficient mice. RESULTS: IL-22- and IL-23-deficient mice exhibited normal susceptibility to infection and oviduct pathology. IL-23 was required for the development of a Chlamydia-specific Th17 response in the lymph nodes and for production of IL-22 and IL-17 in the genital tract. However, influx of Th1 and innate immune cells was not compromised in the absence of IL-23. CONCLUSION: IL-22 and IL-23 play either redundant or minimal roles in the pathogenesis of Chlamydia infection in the mouse model. Induction of Th17-associated cytokines by a Chlamydia vaccine should be avoided as these responses are not central to resolution of infection and have pathologic potential.
Assuntos
Infecções por Chlamydia/imunologia , Chlamydia muridarum/imunologia , Interleucina-17/biossíntese , Interleucina-23/imunologia , Interleucinas/biossíntese , Infecções do Sistema Genital/imunologia , Animais , Células Cultivadas , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/patologia , Feminino , Interleucina-17/imunologia , Interleucina-23/deficiência , Interleucinas/deficiência , Interleucinas/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oviductos/imunologia , Oviductos/patologia , Infecções do Sistema Genital/microbiologia , Infecções do Sistema Genital/patologia , Interleucina 22RESUMO
Influenza infection is widespread in the United States and the world. Despite low mortality rates due to infection, morbidity is common and little is known about the molecular events involved in recovery. Influenza infection results in persistent distal lung remodeling, and the mechanism(s) involved are poorly understood. Recently IL-22 has been found to mediate epithelial repair. We propose that IL-22 is critical for recovery of normal lung function and architecture after influenza infection. Wild-type and IL-22(-/-) mice were infected with influenza A PR8/34 H1N1 and were followed up for up to 21 days post infection. IL-22 receptor was localized to the airway epithelium in naive mice but was expressed at the sites of parenchymal lung remodeling induced by influenza infection. IL-22(-/-) mice displayed exacerbated lung injury compared with wild-type mice, which correlated with decreased lung function 21 days post infection. Epithelial metaplasia was observed in wild-type mice but was not evident in IL-22(-/-) animals that were characterized with an increased fibrotic phenotype. Gene expression analysis revealed aberrant expression of epithelial genes involved in repair processes, among changes in several other biological processes. These data indicate that IL-22 is required for normal lung repair after influenza infection. IL-22 represents a novel pathway involved in interstitial lung disease.
Assuntos
Epitélio/patologia , Epitélio/virologia , Interleucinas/metabolismo , Pulmão/patologia , Pulmão/virologia , Infecções por Orthomyxoviridae/patologia , Cicatrização , Animais , Membrana Basal/metabolismo , Membrana Basal/patologia , Colágeno/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/virologia , Epitélio/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Interleucinas/deficiência , Pulmão/fisiopatologia , Metaplasia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/fisiopatologia , Infecções por Orthomyxoviridae/virologia , Receptores de Interleucina/metabolismo , Testes de Função Respiratória , Transdução de Sinais/genética , Interleucina 22RESUMO
Pulmonary Staphylococcus aureus (SA) infections are a public health concern and a major complication of hyper-IgE syndrome, caused by mutations in STAT3. In contrast to previous findings of skin infection, we observed that clearance of SA from the lung did not require T, B, or NK cells but did require Stat3 activation. Immunohistochemistry showed robust Stat3 phosphorylation in the lung epithelium. We identified that a critical Stat3 target gene in lung epithelium is Reg3g (regenerating islet-derived 3 γ), a gene which is highly expressed in gastrointestinal epithelium but whose role in pulmonary host defense is uncharacterized. Stat3 regulated Reg3g transcription through direct binding at the Reg3g promoter region. Recombinant Reg3γ bound to SA and had both bacteriostatic and bactericidal activity in a dose-dependent fashion. Stat3 inhibition in vivo reduced Reg3g transcripts in the lung, and more importantly, recombinant Reg3γ rescued mice from defective SA clearance. These findings reveal an antibacterial function for lung epithelium through Stat3-mediated induction of Reg3γ.
Assuntos
Staphylococcus aureus Resistente à Meticilina/imunologia , Pneumonia Estafilocócica/imunologia , Proteínas/fisiologia , Fator de Transcrição STAT3/fisiologia , Animais , Receptor gp130 de Citocina/fisiologia , Imunidade Inata , Interleucina-6/biossíntese , Fator Inibidor de Leucemia/biossíntese , Pulmão/imunologia , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas a PancreatiteRESUMO
BACKGROUND: IL-17 is an important cytokine signature of the TH differentiation pathway TH17. This T-cell subset is crucial in mediating autoimmune disease or antimicrobial immunity in animal models, but its presence and role in human disease remain to be completely characterized. OBJECTIVE: We set out to determine the frequency of TH17 cells in patients with cystic fibrosis (CF), a disease in which there is recurrent infection with known pathogens. METHODS: Explanted lungs from patients undergoing transplantation or organ donors (CF samples=18; non-CF, nonbronchiectatic samples=10) were collected. Hilar nodes and parenchymal lung tissue were processed and examined for TH17 signature by using immunofluorescence and quantitative real-time PCR. T cells were isolated and stimulated with antigens from Pseudomonas aeruginosa and Aspergillus species. Cytokine profiles and staining with flow cytometry were used to assess the reactivity of these cells to antigen stimulation. RESULTS: We found a strong IL-17 phenotype in patients with CF compared with that seen in control subjects without CF. Within this tissue, we found pathogenic antigen-responsive CD4+IL-17+ cells. There were double-positive IL-17+IL-22+ cells [TH17(22)], and the IL-22+ population had a higher proportion of memory characteristics. Antigen-specific TH17 responses were stronger in the draining lymph nodes compared with those seen in matched parenchymal lungs. CONCLUSION: Inducible proliferation of TH17(22) with memory cell characteristics is seen in the lungs of patients with CF. The function of these individual subpopulations will require further study regarding their development. T cells are likely not the exclusive producers of IL-17 and IL-22, and this will require further characterization.
Assuntos
Fibrose Cística/patologia , Interleucina-17/imunologia , Interleucinas/imunologia , Pulmão/patologia , Linfonodos/patologia , Células Th17/patologia , Adulto , Idoso , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/farmacologia , Antígenos de Fungos/imunologia , Antígenos de Fungos/farmacologia , Aspergillus/química , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Fibrose Cística/genética , Fibrose Cística/imunologia , Feminino , Expressão Gênica , Humanos , Memória Imunológica , Imunofenotipagem , Interleucina-17/genética , Interleucinas/genética , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Pseudomonas aeruginosa/química , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Interleucina 22RESUMO
IL-6 is a known downstream target of IL-1ß and is consistently increased in serum from patients with NLRP3 inflammasome-mediated conditions. Therefore, IL-6 could be a therapeutic target in the treatment of IL-1ß-provoked inflammation. IL-6 was increased in serum with accompanying neutrophilia in tissues of an inducible mouse model of Muckle-Wells syndrome. However, an IL-6-null background failed to provide phenotypic rescue and did not significantly impact inflammatory cytokine levels. In a second model of IL-1ß-driven inflammation, NLRP3 activation by monosodium urate crystals similarly increased IL-6. Consistent with our Muckle-Wells syndrome model, ablation of IL-6 did not impact an acute neutrophilic response in this in vivo evaluation of gouty arthritis. Taken together, our results indicate that IL-6 is a reliable marker of inflammation, with no direct role in inflammasome-mediated disease.
Assuntos
Proteínas de Transporte , Modelos Animais de Doenças , Inflamassomos , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Animais , Biomarcadores/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Síndromes Periódicas Associadas à Criopirina/imunologia , Síndromes Periódicas Associadas à Criopirina/metabolismo , Síndromes Periódicas Associadas à Criopirina/terapia , Técnicas de Introdução de Genes , Marcação de Genes , Imunofenotipagem , Inflamassomos/genética , Inflamassomos/metabolismo , Inflamassomos/fisiologia , Mediadores da Inflamação/fisiologia , Interleucina-1beta/genética , Interleucina-1beta/fisiologia , Interleucina-6/deficiência , Interleucina-6/fisiologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Reprodutibilidade dos TestesRESUMO
Influenza A virus (IAV) infection is known to induce endoplasmic reticulum (ER) stress, Fas-dependent apoptosis, and TGF-ß production in a variety of cells. However, the relationship between these events in murine primary tracheal epithelial cells (MTECS), which are considered one of the primary sites of IAV infection and replication, is unclear. We show that IAV infection induced ER stress marker activating transcription factor-6 and endoplasmic reticulum protein 57-kD (ERp57), but not C/EBP homologous protein (CHOP). In contrast, the ER stress inducer thapsigargin (THP) increased CHOP. IAV infection activated caspases and apoptosis, independently of Fas and caspase-8, in MTECs. Instead, apoptosis was mediated by caspase-12. A decrease in ERp57 attenuated the IAV burden and decreased caspase-12 activation and apoptosis in epithelial cells. TGF-ß production was enhanced in IAV-infected MTECs, compared with THP or staurosporine. IAV infection caused the activation of c-Jun N-terminal kinase (JNK). Furthermore, IAV-induced TGF-ß production required the presence of JNK1, a finding that suggests a role for JNK1 in IAV-induced epithelial injury and subsequent TGF-ß production. These novel findings suggest a potential mechanistic role for a distinct ER stress response induced by IAV, and a profibrogenic/repair response in contrast to other pharmacological inducers of ER stress. These responses may also have a potential role in acute lung injury, fibroproliferative acute respiratory distress syndrome, and the recently identified H1N1 influenza-induced exacerbations of chronic obstructive pulmonary disease (Wedzicha JA. Proc Am Thorac Soc 2004;1:115-120) and idiopathic pulmonary fibrosis (Umeda Y, et al. Int Med 2010;49:2333-2336).
Assuntos
Apoptose , Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Vírus da Influenza A Subtipo H1N1/fisiologia , Pulmão/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Animais , Caspase 12/metabolismo , Células Cultivadas , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/virologia , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/patologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Estaurosporina/farmacologia , Tapsigargina/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Carga ViralRESUMO
Chronic Obstructive Pulmonary Disease (COPD) is characterized by airspace enlargement and peribronchial lymphoid follicles; however, the immunological mechanisms leading to these pathologic changes remain undefined. Here we show that cigarette smoke is a selective adjuvant that augments in vitro and in vivo Th17, but not Th1, cell differentiation via the aryl hydrocarbon receptor. Smoke exposed IL-17RA(-/-) mice failed to induce CCL2 and MMP12 compared to WT mice. Remarkably, in contrast to WT mice, IL-17RA(-/-) mice failed to develop emphysema after 6 months of cigarette smoke exposure. Taken together, these data demonstrate that cigarette smoke is a potent Th17 adjuvant and that IL-17RA signaling is required for chemokine expression necessary for MMP12 induction and tissue emphysema.
Assuntos
Quimiocina CCL2/metabolismo , Enfisema/imunologia , Regulação da Expressão Gênica/imunologia , Macrófagos/imunologia , Nicotiana/imunologia , Receptores de Interleucina-17/metabolismo , Fumaça/efeitos adversos , Adjuvantes Imunológicos/farmacologia , Animais , Brônquios/citologia , Lavagem Broncoalveolar , Diferenciação Celular/imunologia , Quimiocina CCL2/genética , Enfisema/etiologia , Enfisema/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 3 da Matriz/genética , Camundongos , Mucosa/imunologia , Mucosa/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Análise de Sequência de RNA , Células Th17/citologia , Células Th17/imunologia , Ativação Transcricional/imunologiaRESUMO
γδ T cells are a subset of T cells associated with epithelial mucosal tissues and play a prominent role in both promoting and dampening inflammatory responses to pathogens; in addition, they strongly mediate epithelial repair. By using a bleomycin model of pulmonary fibrosis, we found that γδ T-cell populations dramatically increased after bleomycin administration. To determine the importance of these cells, we exposed mice lacking the δ chain of the γδ T-cell receptor (γδ knockout [KO]) to bleomycin. Pulmonary fibrosis was more severe in γδ KO mice, as measured by collagen deposition (hydroxyproline) and histopathological features. Furthermore, there was no evidence of resolution of the fibrotic response up to 45 days after bleomycin therapy. In contrast to control mice, γδ KO mice had decreased concentrations of IL-6, granulocyte colony stimulating factor, chemokine CXC ligand (CXCL) 1, and interferon inducible protein 10/CXCL10. In vitro culture of γδ T cells purified from lungs 17 days after bleomycin exposure (a time of peak influx of these cells) demonstrated that γδ T cells produced substantial quantities of all four of these cytokines, suggesting that γδ T cells are a predominant source of these proteins. To demonstrate that γδ T cells are effector cells in the fibrotic response, we performed adoptive transfer experiments with γδ T cells sorted from bleomycin-treated lungs; these cells were sufficient to resolve fibrosis in γδ KO mice and restore CXCL10 levels comparable to wild-type mice. Furthermore, overexpression of CXCL10 in the lung decreased the severity of fibrosis seen in the γδ KO mice. Finally, adoptive transfer of γδ T cells from CXCL10(-/-) mice failed to reverse the severe fibrosis in γδ KO mice. These results indicate that γδ T cells promote the resolution of fibrosis through the production of CXCL10.
Assuntos
Quimiocina CXCL10/biossíntese , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/metabolismo , Adenoviridae/genética , Transferência Adotiva , Animais , Bleomicina , Quimiocina CXCL1/metabolismo , Colágeno/metabolismo , Inflamação/complicações , Inflamação/patologia , Interleucina-6/biossíntese , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/complicaçõesRESUMO
A lineage of CD4+ T cells known as Th17 cells, which are derived by exposure of naive CD4+ T cells to IL-6 and TGF-ß, have been implicated in several autoimmune diseases. In this issue of the JCI, studies by Acharya et al. and Melton et al. show that TGF-ß is activated at the DC/CD4+ T cell synapse by αv integrins and that this activation is required for Th17 differentiation and autoimmunity in the central nervous system. Thus, these studies offer a potential therapeutic target in fighting autoimmune diseases.