RESUMEN
Innate lymphoid cells (ILCs) represent innate versions of T helper and cytotoxic T cells that differentiate from committed ILC precursors (ILCPs). How ILCPs give rise to mature tissue-resident ILCs remains unclear. Here, we identify circulating and tissue ILCPs in humans that fail to express the transcription factors and cytokine outputs of mature ILCs but have these signature loci in an epigenetically poised configuration. Human ILCPs robustly generate all ILC subsets in vitro and in vivo. While human ILCPs express low levels of retinoic acid receptor (RAR)-related orphan receptor C (RORC) transcripts, these cells are found in RORC-deficient patients and retain potential for EOMES+ natural killer (NK) cells, interferon gamma-positive (IFN-γ+) ILC1s, interleukin (IL)-13+ ILC2s, and for IL-22+, but not for IL-17A+ ILC3s. Our results support a model of tissue ILC differentiation ("ILC-poiesis"), whereby diverse ILC subsets are generated in situ from systemically distributed ILCPs in response to local environmental signals.
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Linfocitos/citología , Células Madre/citología , Animales , Antígenos CD34/análisis , Diferenciación Celular , Linaje de la Célula , Sangre Fetal/citología , Feto/citología , Humanos , Inmunidad Innata , Interleucina-17 , Hígado/citología , Pulmón/citología , Linfocitos/inmunología , Tejido Linfoide/citología , Ratones , Proteínas Proto-Oncogénicas c-kit/análisis , Transcripción GenéticaRESUMEN
Eosinophils have been previously shown to be able to regulate early humoral responses during systemic vaccination. Here we investigated the role of eosinophils during pulmonary vaccination, comparing vaccine-induced responses in eosinophil-deficient (ΔdblGATA) and wild-type mice using a Th2 adjuvant. We observed that eosinophils were needed to induce a complete vaccine response, thereby eliciting specific antibody-secreting plasma cells in the regional lymph nodes and antibody secretion in the BAL at the early stage of the immune response. Reintroduction of eosinophils in the lungs of ΔdblGATA mice during the priming stage enhanced both specific IgM and IgG plasma cells but not specific IgA plasma cells. Upon vaccination, eosinophils migrated to the lungs and secreted cytokines involved in B-cell activation, which might promote antibody production. Importantly, however, the absence of eosinophils did not impair late immune responses in a prime/boost protocol because, in that setup, we uncovered a compensating mechanism involving a Th17 pathway. In conclusion, our data demonstrate for the first time a new role for eosinophils during lung mucosal vaccination, whereby they accelerate early immune responses (IgM and IgG) while regulating IgA production at the late stages.
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Formación de Anticuerpos , Eosinófilos , Ratones , Animales , Eosinófilos/metabolismo , Pulmón/patología , Vacunación , Inmunoglobulina G , Inmunoglobulina M , Inmunoglobulina A/metabolismo , Ratones Endogámicos BALB C , Inmunidad MucosaRESUMEN
Pseudomonas aeruginosa (P.a) infections are a major public health issue in ventilator-associated pneumoniae, cystic fibrosis, and chronic obstructive pulmonary disease exacerbations. P.a is multidrug resistant, and there is an urgent need to develop new therapeutic approaches. Here, we evaluated the effect of direct pulmonary transplantation of gene-modified (elafin and interleukin [IL]-6) syngeneic macrophages in a mouse model of acute P.a infection. Wild-type (WT) or Elafin-transgenic (eTg) alveolar macrophages (AMs) or bone marrow-derived macrophages (BMDMs) were recovered from bronchoalveolar lavage or generated from WT or eTg mouse bone marrow. Cells were modified with adenovirus IL-6 (Ad-IL-6), characterized in vitro, and transferred by oropharyngeal instillation in the lungs of naive mice. The protective effect was assessed during P.a acute infection (survival studies, mechanistic studies of the inflammatory response). We show that a single bolus of genetically modified syngeneic AMs or BMDMs provided protection in our P.a-induced model. Mechanistically, Elafin-modified AMs had an IL-6-IL-10-IL-4R-IL-22-antimicrobial molecular signature that, in synergy with IL-6, enhanced epithelial cell proliferation and tissue repair in the alveolar unit. We believe that this innovative cell therapy strategy could be of value in acute bacterial infections in the lung.
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Infecciones por Pseudomonas , Animales , Elafina , Inmunoterapia , Interleucina-6/genética , Pulmón/microbiología , Macrófagos , Macrófagos Alveolares , Ratones , Ratones Endogámicos C57BL , Infecciones por Pseudomonas/genética , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/terapia , Pseudomonas aeruginosa/genéticaRESUMEN
Pseudomonas aeruginosa (P.a) is a pathogen causing significant morbidity and mortality, particularly in hospital patients undergoing ventilation and in individuals with cystic fibrosis. Although we and others have investigated mechanisms used by P.a to subvert innate immunity, relatively less is known about the potential strategies used by this bacterium to fight the adaptive immune system and, in particular, T cells. Here, using RAG KO (devoid of 'classical' αß and γδ TCR T lymphocytes) and double RAG γC KO mice (devoid of T, NK and ILC cells), we demonstrate that the lymphocytic compartment is important to combat P.a (PAO1 strain). Indeed, we show that PAO1 load was increased in double RAG γC KO mice. In addition, we show that PAO1 down-regulates IL-23 and IL-22 protein accumulation in the lungs of infected mice while up-regulating their RNA production, thereby pointing towards a specific post-transcriptional regulatory mechanism not affecting other inflammatory mediators. Finally, we demonstrate that an adenovirus-mediated over-expression of IL-1, IL-23 and IL-7 induced lung neutrophil and lymphocytic influx and rescued mice against P.a-induced lethality in all WT, RAG γC KO and RAG γC KO RAG-deficient mice, suggesting that this regimen might be of value in 'locally immunosuppressed' individuals such as cystic fibrosis patients.
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Fibrosis Quística , Infecciones por Pseudomonas , Animales , Fibrosis Quística/genética , Fibrosis Quística/metabolismo , Interleucina-23/metabolismo , Interleucinas , Pulmón/metabolismo , Ratones , Ratones Noqueados , Infecciones por Pseudomonas/metabolismo , Pseudomonas aeruginosa , Interleucina-22RESUMEN
Idiopathic pulmonary fibrosis (IPF) is characterized by the deposition of excessive extracellular matrix and the destruction of lung parenchyma, resulting from an aberrant wound-healing response. Although IPF is often associated with an imbalance in protease activity, the mechanisms underlying the sustained repair mechanisms are not fully understood. Here, we addressed the role of the recently identified, membrane-anchored serine protease human airway trypsin-like protease (HAT). In the present study, we show that both HAT expression and activity were up-regulated in human IPF specimens. Next, adenoviral overexpression of HAT before bleomycin challenge attenuated lung injury as well as extracellular matrix deposition in the bleomycin-induced pulmonary fibrosis model. In vitro, HAT prevented specific fibrosis-associated responses in primary human pulmonary fibroblasts and induced the expression of mediators associated with the prostaglandin E2 pathway. Altogether, our findings suggested that HAT could have a protective role in IPF and other fibrotic lung disorders.-Menou, A., Flajolet, P., Duitmen, J., Justet, A., Moog, S., Jaillet, M., Tabèze, L., Solhonne, B., Garnier, M., Mal, H., Mordant, P., Castier, Y., Cazes, A., Sallenave, J.-M., Mailleux, A. A., Crestani, B. Human airway trypsin-like protease exerts potent, antifibrotic action in pulmonary fibrosis.
Asunto(s)
Lesión Pulmonar/prevención & control , Fibrosis Pulmonar/prevención & control , Serina Endopeptidasas/administración & dosificación , Animales , Antibióticos Antineoplásicos/toxicidad , Bleomicina/toxicidad , Estudios de Casos y Controles , Movimiento Celular , Proliferación Celular , Células Cultivadas , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Fibroblastos/patología , Humanos , Pulmón/efectos de los fármacos , Pulmón/enzimología , Pulmón/patología , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/enzimología , Lesión Pulmonar/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/enzimología , Fibrosis Pulmonar/patología , Serina Endopeptidasas/metabolismo , Transducción de SeñalRESUMEN
BACKGROUND: Pseudomonas aeruginosa lung infections are a huge problem in ventilator-associated pneumonia, cystic fibrosis (CF) and in chronic obstructive pulmonary disease (COPD) exacerbations. This bacterium secretes virulence factors that may subvert host innate immunity. OBJECTIVE: We evaluated the effect of P. aeruginosa elastase LasB, an important virulence factor secreted by the type II secretion system, on ion transport, innate immune responses and epithelial repair, both in vitro and in vivo. METHODS: Wild-type (WT) or cystic fibrosis transmembrane conductance regulator (CFTR)-mutated epithelial cells (cell lines and primary cells from patients) were treated with WT or ΔLasB pseudomonas aeruginosa O1 (PAO1) secretomes. The effect of LasB and PAO1 infection was also assessed in vivo in murine models. RESULTS: We showed that LasB was the most abundant protein in WT PAO1 secretomes and that it decreased epithelial CFTR expression and activity. In airway epithelial cell lines and primary bronchial epithelial cells, LasB degraded the immune mediators interleukin (IL)-6 and trappin-2, an important epithelial-derived antimicrobial molecule. We further showed that an IL-6/STAT3 signalling pathway was downregulated by LasB, resulting in inhibition of epithelial cell repair. In mice, intranasally instillated LasB induced significant weight loss, inflammation, injury and death. By contrast, we showed that overexpression of IL-6 and trappin-2 protected mice against WT-PAO1-induced death, by upregulating IL-17/IL-22 antimicrobial and repair pathways. CONCLUSIONS: Our data demonstrate that PAO1 LasB is a major P. aeruginosa secreted factor that modulates ion transport, immune response and tissue repair. Targeting this virulence factor or upregulating protective factors such as IL-6 or antimicrobial molecules such as trappin-2 could be beneficial in P. aeruginosa-infected individuals.
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Proteínas Bacterianas , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Fibrosis Quística/inmunología , Células Epiteliales/fisiología , Inmunidad Innata/fisiología , Interleucina-6/fisiología , Metaloendopeptidasas , Animales , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones TransgénicosRESUMEN
More than 2% of all human genes are coding for a complex system of more than 700 proteases and protease inhibitors. Among them, serine proteases play extraordinary, diverse functions in different physiological and pathological processes. The human airway trypsin-like protease (HAT), also referred to as TMPRSS11D and serine 11D, belongs to the emerging family of cell surface proteolytic enzymes, the type II transmembrane serine proteases (TTSPs). Through the cleavage of its four major identified substrates, HAT triggers specific responses, notably in epithelial cells, within the pericellular and extracellular environment, including notably inflammatory cytokine production, inflammatory cell recruitment, or anticoagulant processes. This review summarizes the potential role of this recently described protease in mediating cell surface proteolytic events, to highlight the structural features, proteolytic activity, and regulation, including the expression profile of HAT, and discuss its possible roles in respiratory physiology and disease.
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Trastornos Respiratorios/enzimología , Serina Endopeptidasas/metabolismo , Animales , Biocatálisis , Desarrollo Fetal , Humanos , Modelos Biológicos , Trastornos Respiratorios/embriología , Trastornos Respiratorios/patología , Serina Endopeptidasas/químicaRESUMEN
Fibroblast growth factor 9 (FGF9) is necessary for fetal lung development and is expressed by epithelium and mesothelium. We evaluated the role of FGF9 overexpression on adenoviral-induced pleural injury in vivo and determined the biological effects of FGF9 on mesothelial cells in vitro. We assessed the expression of FGF9 and FGF receptors by mesothelial cells in both human and mouse lungs. Intrapleural injection of an adenovirus expressing human FGF9 (AdFGF9) or a control adenovirus (AdCont) was performed. Mice were euthanized at days 3, 5, and 14 Expression of FGF9 and markers of inflammation and myofibroblastic differentiation was studied by qPCR and immunohistochemistry. In vitro, rat mesothelial cells were stimulated with FGF9 (20 ng/ml), and we assessed its effect on proliferation, survival, migration, and differentiation. FGF9 was expressed by mesothelial cells in human idiopathic pulmonary fibrosis. FGF receptors, mainly FGFR3, were expressed by mesothelial cells in vivo in humans and mice. AdCont instillation induced diffuse pleural thickening appearing at day 5, maximal at day 14 The altered pleura cells strongly expressed α-smooth muscle actin and collagen. AdFGF9 injection induced maximal FGF9 expression at day 5 that lasted until day 14 FGF9 overexpression prevented pleural thickening, collagen and fibronectin accumulation, and myofibroblastic differentiation of mesothelial cells. In vitro, FGF9 decreased mesothelial cell migration and inhibited the differentiating effect of transforming growth factor-ß1. We conclude that FGF9 has a potential antifibrotic effect on mesothelial cells.
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Adenoviridae/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Factor 9 de Crecimiento de Fibroblastos/farmacología , Fibrosis Pulmonar Idiopática/virología , Pulmón/patología , Animales , Diferenciación Celular , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Epitelio/patología , Epitelio/virología , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/prevención & control , Pulmón/virología , Ratones Endogámicos C57BL , Pleura/efectos de los fármacos , RatasRESUMEN
BACKGROUND: Different studies have described the successful use of recombinant lactic acid bacteria (recLAB) to deliver anti-inflammatory molecules at the mucosal level to treat Inflammatory Bowel Disease (IBD). METHODS: In order to identify the best strategy to treat IBD using recLAB, we compared the efficacy of different recombinant strains of Lactococcus lactis (the model LAB) secreting two types of anti-inflammatory molecules: cytokines (IL-10 and TGF-ß1) and serine protease inhibitors (Elafin and Secretory Leukocyte Protease Inhibitor: SLPI), using a dextran sulfate sodium (DSS)-induced mouse model of colitis. RESULTS: Our results show that oral administration of recombinant L. lactis strains expressing either IL-10 or TGF-ß1 display moderate anti-inflammatory effects in inflamed mice and only for some clinical parameters. In contrast, delivery of either serine protease inhibitors Elafin or SLPI by recLAB led to a significant reduction of intestinal inflammation for all clinical parameters tested. Since the best results were obtained with Elafin-producing L. lactis strain, we then tried to enhance Elafin expression and hence its delivery rate by producing it in a L. lactis mutant strain inactivated in its major housekeeping protease, HtrA. Strikingly, a higher reduction of intestinal inflammation in DSS-treated mice was observed with the Elafin-overproducing htrA strain suggesting a dose-dependent Elafin effect. CONCLUSIONS: Altogether, these results strongly suggest that serine protease inhibitors are the most efficient anti-inflammatory molecules to be delivered by recLAB at the mucosal level for IBD treatment.
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Interleucina-10/metabolismo , Lactococcus lactis/metabolismo , Inhibidores de Serina Proteinasa/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Administración Oral , Animales , Colitis/microbiología , Colitis/patología , Colitis/terapia , Modelos Animales de Enfermedad , Elafina/genética , Elafina/metabolismo , Expresión Génica/efectos de los fármacos , Interleucina-10/genética , Ratones , Ratones Endogámicos C57BL , Nisina/farmacología , Inhibidor Secretorio de Peptidasas Leucocitarias/genética , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo , Inhibidores de Serina Proteinasa/genética , Factor de Crecimiento Transformador beta/genéticaRESUMEN
BACKGROUND: The lung epithelium constitutes the first barrier against invading pathogens and also a major surface potentially exposed to nanoparticles. In order to ensure and preserve lung epithelial barrier function, the alveolar compartment possesses local defence mechanisms that are able to control bacterial infection. For instance, alveolar macrophages are professional phagocytic cells that engulf bacteria and environmental contaminants (including nanoparticles) and secrete pro-inflammatory cytokines to effectively eliminate the invading bacteria/contaminants. The consequences of nanoparticle exposure in the context of lung infection have not been studied in detail. Previous reports have shown that sequential lung exposure to nanoparticles and bacteria may impair bacterial clearance resulting in increased lung bacterial loads, associated with a reduction in the phagocytic capacity of alveolar macrophages. RESULTS: Here we have studied the consequences of SiO2 nanoparticle exposure on Pseudomonas aeruginosa clearance, Pseudomonas aeruginosa-induced inflammation and lung injury in a mouse model of acute pneumonia. We observed that pre-exposure to SiO2 nanoparticles increased mice susceptibility to lethal pneumonia but did not modify lung clearance of a bioluminescent Pseudomonas aeruginosa strain. Furthermore, internalisation of SiO2 nanoparticles by primary alveolar macrophages did not reduce the capacity of the cells to clear Pseudomonas aeruginosa. In our murine model, SiO2 nanoparticle pre-exposure preferentially enhanced Pseudomonas aeruginosa-induced lung permeability (the latter assessed by the measurement of alveolar albumin and IgM concentrations) rather than contributing to Pseudomonas aeruginosa-induced lung inflammation (as measured by leukocyte recruitment and cytokine concentration in the alveolar compartment). CONCLUSIONS: We show that pre-exposure to SiO2 nanoparticles increases mice susceptibility to lethal pneumonia but independently of macrophage phagocytic function. The deleterious effects of SiO2 nanoparticle exposure during Pseudomonas aeruginosa-induced pneumonia are related to alterations of the alveolar-capillary barrier rather than to modulation of the inflammatory responses.
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Permeabilidad Capilar/efectos de los fármacos , Nanopartículas/toxicidad , Neumonía Bacteriana/inducido químicamente , Infecciones por Pseudomonas/inducido químicamente , Pseudomonas aeruginosa/patogenicidad , Alveolos Pulmonares/efectos de los fármacos , Óxidos de Selenio/toxicidad , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/microbiología , Citocinas/análisis , Inmunoglobulina M/análisis , Exposición por Inhalación , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/inmunología , Masculino , Ratones Endogámicos C57BL , Nanopartículas/química , Tamaño de la Partícula , Fagocitosis/efectos de los fármacos , Neumonía Bacteriana/inmunología , Neumonía Bacteriana/microbiología , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Alveolos Pulmonares/irrigación sanguínea , Óxidos de Selenio/química , Propiedades de Superficie , Análisis de SupervivenciaRESUMEN
MUC5AC, a major gel-forming mucin expressed in the lungs, is secreted at increased rates in response to infectious agents, implying that mucins exert a protective role against inhaled pathogens. However, epidemiological and pathological studies suggest that excessive mucin secretion causes airways obstruction and inflammation. To determine whether increased MUC5AC secretion alone produces airway obstruction and/or inflammation, we generated a mouse model overexpressing Muc5ac mRNA ~20-fold in the lungs, using the rCCSP promoter. The Muc5ac cDNA was cloned from mouse lungs and tagged internally with GFP. Bronchoalveolar lavage fluid (BALF) analysis demonstrated an approximate 18-fold increase in Muc5ac protein, which formed high-molecular-weight polymers. Histopathological studies and cell counts revealed no airway mucus obstruction or inflammation in the lungs of Muc5ac-transgenic (Muc5ac-Tg) mice. Mucus clearance was preserved, implying that the excess Muc5ac secretion produced an "expanded" rather than more concentrated mucus layer, a prediction confirmed by electron microscopy. To test whether the larger mucus barrier conferred increased protection against pathogens, Muc5ac-Tg animals were challenged with PR8/H1N1 influenza viruses and showed significant decreases in infection and neutrophilic responses. Plaque assay experiments demonstrated that Muc5ac-Tg BALF and purified Muc5ac reduced infection, likely via binding to α2,3-linked sialic acids, consistent with influenza protection in vivo. In conclusion, the normal mucus transport and absence of a pulmonary phenotype in Muc5ac-Tg mice suggests that mucin hypersecretion alone is not sufficient to trigger luminal mucus plugging or airways inflammation/goblet cell hyperplasia. In contrast, increased Muc5ac secretion appears to exhibit a protective role against influenza infection.
Asunto(s)
Modelos Animales de Enfermedad , Subtipo H1N1 del Virus de la Influenza A/inmunología , Pulmón/inmunología , Mucina 5AC/inmunología , Infecciones por Orthomyxoviridae/inmunología , Animales , Secuencia de Bases , Western Blotting , Líquido del Lavado Bronquioalveolar/química , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Interacciones Huésped-Patógeno/inmunología , Humanos , Subtipo H1N1 del Virus de la Influenza A/fisiología , Pulmón/metabolismo , Pulmón/virología , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Confocal , Microscopía Electrónica , Datos de Secuencia Molecular , Mucina 5AC/genética , Mucina 5AC/metabolismo , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/virología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
A deficit in early clearance of Pseudomonas aeruginosa (P. aeruginosa) is crucial in nosocomial pneumonia and in chronic lung infections. Few studies have addressed the role of Toll-like receptors (TLRs), which are early pathogen associated molecular pattern receptors, in pathogen uptake and clearance by alveolar macrophages (AMs). Here, we report that TLR5 engagement is crucial for bacterial clearance by AMs in vitro and in vivo because unflagellated P. aeruginosa or different mutants defective in TLR5 activation were resistant to AM phagocytosis and killing. In addition, the clearance of PAK (a wild-type P. aeruginosa strain) by primary AMs was causally associated with increased IL-1ß release, which was dramatically reduced with PAK mutants or in WT PAK-infected primary TLR5(-/-) AMs, demonstrating the dependence of IL-1ß production on TLR5. We showed that this IL-1ß production was important in endosomal pH acidification and in inducing the killing of bacteria by AMs through asparagine endopeptidase (AEP), a key endosomal cysteine protease. In agreement, AMs from IL-1R1(-/-) and AEP(-/-) mice were unable to kill P. aeruginosa. Altogether, these findings demonstrate that TLR5 engagement plays a major role in P. aeruginosa internalization and in triggering IL-1ß formation.
Asunto(s)
Endopeptidasas/metabolismo , Interleucina-1beta/metabolismo , Macrófagos Alveolares/inmunología , Fagocitosis , Pseudomonas aeruginosa/inmunología , Receptor Toll-Like 5/fisiología , Animales , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Endogámicos C57BLRESUMEN
Serine protease inhibitor elafin (E) and its precursor, trappin-2 (Tr), have been associated with mucosal resistance to HIV-1 infection. We recently showed that Tr/E are among principal anti-HIV-1 molecules in cervicovaginal lavage (CVL) fluid, that E is â¼130 times more potent than Tr against HIV-1, and that Tr/E inhibited HIV-1 attachment and transcytosis across human genital epithelial cells (ECs). Since herpes simplex virus 2 (HSV-2) is a major sexually transmitted infection and risk factor for HIV-1 infection and transmission, we assessed Tr/E contribution to defense against HSV-2. Our in vitro studies demonstrated that pretreatment of endometrial (HEC-1A) and endocervical (End1/E6E7) ECs with human Tr-expressing adenovirus (Ad/Tr) or recombinant Tr/E proteins before or after HSV-2 infection resulted in significantly reduced virus titers compared to those of controls. Interestingly, E was â¼7 times more potent against HSV-2 infection than Tr. Conversely, knockdown of endogenous Tr/E by small interfering RNA (siRNA) significantly increased HSV-2 replication in genital ECs. Recombinant Tr and E reduced viral attachment to genital ECs by acting indirectly on cells. Further, lower viral replication was associated with reduced secretion of proinflammatory interleukin 8 (IL-8) and tumor necrosis factor alpha (TNF-α) and decreased NF-κB nuclear translocation. Additionally, protected Ad/Tr-treated ECs demonstrated enhanced interferon regulatory factor 3 (IRF3) nuclear translocation and increased antiviral IFN-ß in response to HSV-2. Lastly, in vivo studies of intravaginal HSV-2 infection in Tr-transgenic mice (Etg) showed that despite similar virus replication in the genital tract, Etg mice had reduced viral load and TNF-α in the central nervous system compared to controls. Collectively, this is the first experimental evidence highlighting anti-HSV-2 activity of Tr/E in female genital mucosa.
Asunto(s)
Elafina/farmacología , Células Epiteliales/virología , Herpes Genital/prevención & control , Herpesvirus Humano 2/efectos de los fármacos , Carga Viral/efectos de los fármacos , Adenoviridae , Análisis de Varianza , Animales , Western Blotting , Línea Celular Tumoral , Chlorocebus aethiops , Cartilla de ADN/genética , Elafina/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente , Técnicas de Silenciamiento del Gen , Vectores Genéticos/genética , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interleucina-8/metabolismo , Ratones , Ratones Transgénicos , FN-kappa B/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Sales de Tetrazolio , Tiazoles , Factor de Necrosis Tumoral alfa/metabolismo , Células Vero , Acoplamiento Viral/efectos de los fármacos , Replicación Viral/efectos de los fármacosRESUMEN
RATIONALE: Cystic fibrosis transmembrane conductance regulator (CFTR) protein is a chloride channel regulating fluid homeostasis at epithelial surfaces. Its loss of function induces hypohydration, mucus accumulation, and bacterial infections in CF and potentially other lung chronic diseases. OBJECTIVES: To test whether neutrophil elastase (NE) and neutrophil-mediated inflammation negatively impact CFTR structure and function, in vitro and in vivo. METHODS: Using an adenovirus-CFTR overexpression approach, we showed that NE degrades wild-type (WT)- and ΔF508-CFTR in vitro and WT-CFTR in mice through a new pathway involving the activation of intracellular calpains. MEASUREMENTS AND MAIN RESULTS: CFTR degradation triggered a loss of function, as measured in vitro by channel patch-clamp and in vivo by nasal potential recording in mice. Importantly, this mechanism was also shown to be operative in a Pseudomonas aeruginosa lung infection murine model, and was NE-dependent, because CFTR integrity was significantly protected in NE(-/-) mice compared with WT mice. CONCLUSIONS: These data provide a new mechanism and show for the first time a link between NE-calpains activation and CFTR loss of function in bacterial lung infections relevant to CF and to other chronic inflammatory lung conditions.
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Calpaína/fisiología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Elastasa de Leucocito/fisiología , Animales , Calpaína/metabolismo , Canales de Cloruro/fisiología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Epitelio/fisiología , Humanos , Elastasa de Leucocito/metabolismo , Pulmón/metabolismo , Pulmón/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Técnicas de Placa-Clamp , Neumonía Bacteriana/etiología , Neumonía Bacteriana/fisiopatología , Infecciones por Pseudomonas/etiología , Infecciones por Pseudomonas/fisiopatologíaRESUMEN
Introduction: Cystic Fibrosis (CF) is the commonest genetically inherited disease (1 in 4,500 newborns) and 70% of people with CF (pwCF) harbour the F508Del mutation, resulting in misfolding and incorrect addressing of the channel CFTR to the epithelial membrane and subsequent dysregulation of fluid homeostasis. Although studies have underscored the importance and over-activation of myeloid cells, and in particular neutrophils in the lungs of people with CF (pwCF), relatively less emphasis has been put on the potential immunological bias in CF blood cells, at homeostasis or following stimulation/infection. Methods: Here, we revisited, in an exhaustive fashion, in pwCF with mild disease (median age of 15, median % FEV1 predicted = 87), whether their PBMCs, unprimed or primed with a 'non specific' stimulus (PMA+ionomycin mix) and a 'specific' one (live P.a =PAO1 strain), were differentially activated, compared to healthy controls (HC) PBMCs. Results: 1) we analysed the lymphocytic and myeloid populations present in CF and Control PBMCs (T cells, NKT, Tgd, ILCs) and their production of the signature cytokines IFN-g, IL-13, IL-17, IL-22. 2) By q-PCR, ELISA and Luminex analysis we showed that CF PBMCs have increased background cytokines and mediators production and a partial functional tolerance phenotype, when restimulated. 3) we showed that CF PBMCs low-density neutrophils release higher levels of granule components (S100A8/A9, lactoferrin, MMP-3, MMP-7, MMP-8, MMP-9, NE), demonstrating enhanced exocytosis of potentially harmful mediators. Discussion: In conclusion, we demonstrated that functional lymphoid tolerance and enhanced myeloid protease activity are key features of cystic fibrosis PBMCs.
Asunto(s)
Fibrosis Quística , Recién Nacido , Humanos , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Citocinas , Linfocitos , PulmónRESUMEN
Silver nanoparticles (AgNPs) are a potential antiviral agent due to their ability to disrupt the viral particle or alter the virus metabolism inside the host cell. In vitro, AgNPs exhibit antiviral activity against the most common human respiratory viruses. However, their capacity to modulate immune responses during respiratory viral infections has yet to be explored. This study demonstrates that administering AgNPs directly into the lungs prior to infection can reduce viral loads and therefore virus-induced cytokines in mice infected with influenza virus or murine pneumonia virus. The prophylactic effect was diminished in mice with depleted lymphoid cells. We showed that AgNPs-treatment resulted in the recruitment and activation of lymphocytes in the lungs, particularly natural killer (NK) cells. Mechanistically, AgNPs enhanced the ability of alveolar macrophages to promote both NK cell migration and IFN-γ production. By contrast, following infection, in mice treated with AgNPs, NK cells exhibited decreased activation, indicating that these nanoparticles can regulate the potentially deleterious activation of these cells. Overall, the data suggest that AgNPs may possess prophylactic antiviral properties by recruiting and controlling the activation of lymphoid cells through interaction with alveolar macrophages.
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Introduction: Although many studies have underscored the importance of T cells, phenotypically and functionally, fewer have studied the functions of myeloid cells in COVID disease. In particular, the potential role of myeloid cells such as monocytes and low-density neutrophils (LDNs) in innate responses and particular in the defense against secondary bacterial infections has been much less documented. Methods: Here, we compared, in a longitudinal study, healthy subjects, idiopathic fibrosis patients, COVID patients who were either hospitalized/moderate (M-) or admitted to ICU (COV-ICU) and patients in ICU hospitalized for other reasons (non-COV-ICU). Results: We show that COVID patients have an increased proportion of low-density neutrophils (LDNs), which produce high levels of proteases (particularly, NE, MMP-8 and MMP-9) (unlike non-COV-ICU patients), which are partly responsible for causing type II alveolar cell damage in co-culture experiments. In addition, we showed that M- and ICU-COVID monocytes had reduced responsiveness towards further live Pseudomonas aeruginosa (PAO1 strain) infection, an important pathogen colonizing COVID patients in ICU, as assessed by an impaired secretion of myeloid cytokines (IL-1, TNF, IL-8, ). By contrast, lymphoid cytokines (in particular type 2/type 3) levels remained high, both basally and post PAO1 infection, as reflected by the unimpaired capacity of T cells to proliferate, when stimulated with anti-CD3/CD28 beads. Discussion: Overall, our results demonstrate that COVID circulatory T cells have a biased type 2/3 phenotype, unconducive to proper anti-viral responses and that myeloid cells have a dual deleterious phenotype, through their LDN-mediated damaging effect on alveolar cells and their impaired responsiveness (monocyte-mediated) towards bacterial pathogens such as P. aeruginosa.
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COVID-19 , Monocitos , Neutrófilos , Infecciones por Pseudomonas , Pseudomonas aeruginosa , SARS-CoV-2 , Humanos , COVID-19/inmunología , Pseudomonas aeruginosa/inmunología , Monocitos/inmunología , Masculino , Femenino , Persona de Mediana Edad , SARS-CoV-2/inmunología , SARS-CoV-2/fisiología , Infecciones por Pseudomonas/inmunología , Neutrófilos/inmunología , Anciano , Citocinas/metabolismo , Citocinas/inmunología , Adulto , Estudios Longitudinales , Leucocitos Mononucleares/inmunología , Pulmón/inmunología , Pulmón/patología , Pulmón/microbiologíaRESUMEN
Epidemiological studies showed a positive association between exposure to PM2.5 and the severity of influenza virus infection. However, the mechanisms by which PM2.5 can disrupt antiviral defence are still unclear. From this perspective, the objective of this study was to evaluate the effects of PM2.5 on antiviral signalling in the respiratory epithelium using the bronchial Calu-3 cell line grown at the air-liquid interface. Pre-exposure to PM2.5 before infection with the influenza virus was investigated, as well as a co-exposure. Although a physical interaction between the virus and the particles seems possible, no effect of PM2.5 on viral replication was observed during co-exposure, although a downregulation of IFN-ß release was associated to PM2.5 exposure. However, pre-exposure slightly increased the viral nucleoprotein production and the pro-inflammatory response. Conversely, the level of the myxovirus resistance protein A (MxA), an interferon-stimulated gene (ISG) induced by IFN-ß, was reduced. Therefore, these results suggest that pre-exposure to PM2.5 could alter the antiviral response of bronchial epithelial cells, increasing their susceptibility to viral infection.
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Gripe Humana , Orthomyxoviridae , Virosis , Humanos , Interferones , Gripe Humana/genética , Gripe Humana/metabolismo , Mucosa Respiratoria , Antivirales , Epitelio/metabolismo , Material Particulado/toxicidadRESUMEN
Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that was related to cancer development and metastasis dissemination on several types of tumors. However, it is not known the effect of SLPI on mammary and colon tumors. The aim of this study was to examine the effect of SLPI on mammary and colon tumor growth. The effect of SLPI was tested on in vitro cell apoptosis and in vivo tumor growth experiments. SLPI over-expressing human and murine mammary and colon tumor cells were generated by gene transfection. The administration of murine mammary tumor cells over-expressing high levels of SLPI did not develop tumors in mice. On the contrary, the administration of murine colon tumor cells over-expressing SLPI, developed faster tumors than control cells. Intratumoral, but not intraperitoneal administration of SLPI, delayed the growth of tumors and increased the survival of mammary but not colon tumor bearing mice. In vitro culture of mammary tumor cell lines treated with SLPI, and SLPI producer clones were more prone to apoptosis than control cells, mainly under serum deprivation culture conditions. Herein we demonstrated that SLPI induces the apoptosis of mammary tumor cells in vitro and decreases the mammary but not colon tumor growth in vivo. Therefore, SLPI may be a new potential therapeutic tool for certain tumors, such as mammary tumors.
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Neoplasias de la Mama/metabolismo , Neoplasias del Colon/metabolismo , Neoplasias Mamarias Animales/metabolismo , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Femenino , Silenciador del Gen , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Mamarias Animales/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Inhibidor Secretorio de Peptidasas Leucocitarias/farmacología , Transfección , Neoplasias del Cuello Uterino/metabolismoRESUMEN
Airway inflammation plays a major role in the pathogenesis of influenza viruses and can lead to a fatal outcome. One of the challenging objectives in the field of influenza research is the identification of the molecular bases associated to the immunopathological disorders developed during infection. While its precise function in the virus cycle is still unclear, the viral protein PB1-F2 is proposed to exert a deleterious activity within the infected host. Using an engineered recombinant virus unable to express PB1-F2 and its wild-type homolog, we analyzed and compared the pathogenicity and host response developed by the two viruses in a mouse model. We confirmed that the deletion of PB1-F2 renders the virus less virulent. The global transcriptomic analyses of the infected lungs revealed a potent impact of PB1-F2 on the response developed by the host. Thus, after two days post-infection, PB1-F2 invalidation severely decreased the number of genes activated by the host. PB1-F2 expression induced an increase in the number and level of expression of activated genes linked to cell death, inflammatory response and neutrophil chemotaxis. When generating interactive gene networks specific to PB1-F2, we identified IFN-γ as a central regulator of PB1-F2-regulated genes. The enhanced cell death of airway-recruited leukocytes was evidenced using an apoptosis assay, confirming the pro-apoptotic properties of PB1-F2. Using a NF-kB luciferase adenoviral vector, we were able to quantify in vivo the implication of NF-kB in the inflammation mediated by the influenza virus infection; we found that PB1-F2 expression intensifies the NF-kB activity. Finally, we quantified the neutrophil recruitment within the airways, and showed that this type of leukocyte is more abundant during the infection of the wild-type virus. Collectively, these data demonstrate that PB1-F2 strongly influences the early host response during IAV infection and provides new insights into the mechanisms by which PB1-F2 mediates virulence.