RESUMO
BACKGROUND: Despite the fact that vaccines save 2-3 million lives worldwide every year, a percentage of children are not getting appropriately vaccinated, thus leading to disease outbreaks. One of the major reasons of low vaccine uptake in Europe is vaccine hesitancy, contributing to the recent measles outbreaks. Monitoring of vaccine hesitancy is valuable in early identification of vaccine concerns. METHODS: We performed an eighteen country European survey on parents' attitudes and behaviors regarding their children's immunization. Parents having at least one child 1-4 years old were mostly recruited by primary care paediatricians to reply to a web-based questionnaire. The questionnaire was developed by the European Academy of Paediatrics Research in Ambulatory Setting Network steering committee, based on similar surveys. An individual level hesitancy score was constructed using the answers to 21 questions, and correlations of the score with socio-demographic characteristics and types of providers were explored. To assess inter country differences, a country level self -reported confidence was defined. RESULTS: Fifty six percent and 24% of 5736 respondents defined themselves as "not at all hesitant", and "somewhat hesitant", respectively. Parents who consulted general practitioners were more hesitant than parents who consulted pediatricians (p < 0.05). Consultation with homeopathists was associated with the highest reported hesitancy (p < 0.05). Vaccine confidence was highest in Portugal and Cyprus, and lowest in Bulgaria and Poland. CONCLUSION: The majority of parents in Europe believe in the importance of childhood vaccination. However, significant lack of confidence was found in certain European countries, highlighting the need for continuous monitoring, awareness and response plans. The possible influence of different types of healthcare providers on parental decisions demonstrated for the first time in our survey, calls for further research. Monitoring and continuous medical education efforts aimed mostly at those professionals who might not be likely to recommend vaccination are suggested.
Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pais/psicologia , Vacinação/psicologia , Vacinas , Bulgária , Pré-Escolar , Chipre , Europa (Continente) , Humanos , Lactente , Polônia , Portugal , Inquéritos e QuestionáriosRESUMO
Mutations in GLE1 underlie Lethal Congenital Contracture syndrome (LCCS) and Lethal Arthrogryposis with Anterior Horn Cell Disease (LAAHD). Both LCCS and LAAHD are characterized by reduced fetal movements, congenital contractures, and a severe form of motor neuron disease that results in fetal death or death in the perinatal period, respectively. We identified bi-allelic mutations in GLE1 in two unrelated individuals with motor delays, feeding difficulties, and respiratory insufficiency who survived beyond the perinatal period. Each affected child had missense variants predicted to result in amino acid substitutions near the C-terminus of GLE1 that are predicted to disrupt protein-protein interaction or GLE1 protein targeting. We hypothesize that mutations that preserve function of the coiled-coil domain of GLE1 cause LAAHD whereas mutations that abolish the function of the coiled-coil domain cause LCCS. The phenotype of LAAHD is now expanded to include multiple individuals surviving into childhood suggesting that LAAHD is a misnomer and should be re-named Arthrogryposis with Anterior Horn Cell Disease (AAHD).
Assuntos
Artrogripose/genética , Transtornos Motores/genética , Doença dos Neurônios Motores/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Artrogripose/fisiopatologia , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Transtornos Motores/fisiopatologia , Doença dos Neurônios Motores/fisiopatologia , Mutação , Linhagem , GravidezRESUMO
In human lung fibrotic lesions, fibroblasts were shown to be closely associated with immature dendritic cell (DC) accumulation. The aim of the present pilot study was to characterize the role of pulmonary fibroblasts on DC phenotype and function, using co-culture of lung fibroblasts from patients with idiopathic pulmonary fibrosis (IPF) and from control patients, with a DC cell line MUTZ-3. We observed that co-culture of lung control and IPF fibroblasts with DCs reduced the expression of specific DC markers and down-regulated their T-cell stimulatory activity. This suggests that pulmonary fibroblasts might sustain chronic inflammation in the fibrotic lung by maintaining in situ a pool of immature DCs.
Assuntos
Comunicação Celular/imunologia , Células Dendríticas/citologia , Fibroblastos/citologia , Fibroblastos/imunologia , Pulmão/citologia , Pulmão/imunologia , Proliferação de Células/fisiologia , Células Cultivadas , Citocinas/imunologia , Humanos , Técnicas In Vitro , Fenótipo , Projetos PilotoRESUMO
BACKGROUND: Fibrocytes are circulating precursors for fibroblasts. Blood fibrocytes are increased in patients with idiopathic pulmonary fibrosis (IPF). The aim of this study was to determine whether alveolar fibrocytes are detected in broncho-alveolar lavage (BAL), to identify their prognostic value, and their potential association with culture of fibroblasts from BAL. METHODS: We quantified fibrocytes in BAL from 26 patients with IPF, 9 patients with Systemic Sclerosis(SSc)-interstitial lung disease (ILD), and 11 controls. BAL cells were cultured to isolate alveolar fibroblasts. RESULTS: Fibrocytes were detected in BAL in 14/26 IPF (54%) and 5/9 SSc patients (55%), and never in controls. Fibrocytes were in median 2.5% [0.4-19.7] and 3.0% [2.7-3.7] of BAL cells in IPF and SSc-ILD patients respectively. In IPF patients, the number of alveolar fibrocytes was correlated with the number of alveolar macrophages and was associated with a less severe disease but not with a better outcome. Fibroblasts were cultured from BAL in 12/26 IPF (46%), 5/9 SSc-ILD (65%) and never in controls. The detection of BAL fibrocytes did not predict a positive culture of fibroblasts. CONCLUSION: Fibrocytes were detected in BAL fluid in about half of the patients with IPF and SSc-ILD. Their number was associated with less severe disease in IPF patients and did not associate with the capacity to grow fibroblasts from BAL fluid.
Assuntos
Fibroblastos/patologia , Fibrose Pulmonar Idiopática/patologia , Alvéolos Pulmonares/patologia , Escleroderma Sistêmico/patologia , Idoso , Idoso de 80 Anos ou mais , Lavagem Broncoalveolar , Contagem de Células , Feminino , Humanos , Fibrose Pulmonar Idiopática/terapia , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/terapia , Fatores de TempoRESUMO
Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by myofibroblast proliferation. Transition of epithelial/mesothelial cells into myofibroblasts [epithelial-to-mesenchymal transition (EMT)] occurs under the influence of transforming growth factor (TGF)-ß1, with Snail being a major transcription factor. We study here the role of the heat-shock protein HSP27 in fibrogenesis and EMT. In vitro, we have up- and down-modulated HSP27 expression in mesothelial and epithelial cell lines and studied the expression of different EMT markers induced by TGF-ß1. In vivo, we inhibited HSP27 with the antisense oligonucleotide OGX-427 (in phase II clinical trials as anticancer agent) in our rat subpleural/pulmonary fibrosis models. We demonstrate that HSP27 is strongly expressed during the fibrotic process in patients with IPF and in different in vivo models. We showed that HSP27 binds to and stabilizes Snail and consequently induces EMT. Conversely, HSP27 knockdown leads to Snail proteasomal degradation, thus inhibiting TGF-ß1-induced EMT. Inhibition of HSP27 with OGX-427 efficiently blocks EMT and fibrosis development. Controls in vivo were an empty adenovirus that did not induce fibrosis and a control antisense oligonucleotide. The present work opens the possibility of a new therapeutic use for HSP27 inhibitors against IPF, for which there is no conclusively effective treatment.
Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Proteínas de Choque Térmico HSP27/antagonistas & inibidores , Caramujos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Caderinas/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Fibrose/metabolismo , Humanos , Oligonucleotídeos Antissenso/farmacologia , Ratos , Ratos Sprague-Dawley , Tionucleotídeos/farmacologia , Fatores de Transcrição/metabolismoRESUMO
Idiopathic pulmonary fibrosis (IPF) is a devastating disease of unknown cause. Key signaling developmental pathways are aberrantly expressed in IPF. The hedgehog pathway plays a key role during fetal lung development and may be involved in lung fibrogenesis. We determined the expression pattern of several Sonic hedgehog (SHH) pathway members in normal and IPF human lung biopsies and primary fibroblasts. The effect of hedgehog pathway inhibition was assayed by lung fibroblast proliferation and differentiation with and without transforming growth factor (TGF)-ß1. We showed that the hedgehog pathway was reactivated in the IPF lung. Importantly, we deciphered the cross talk between the hedgehog and TGF-ß pathway in human lung fibroblasts. TGF-ß1 modulated the expression of key components of the hedgehog pathway independent of Smoothened, the obligatory signal transducer of the pathway. Smoothened was required for TGF-ß1-induced myofibroblastic differentiation of control fibroblasts, but differentiation of IPF fibroblasts was partially resistant to Smoothened inhibition. Furthermore, functional hedgehog pathway machinery from the primary cilium, as well as GLI-dependent transcription in the nucleus, was required for the TGF-ß1 effects on normal and IPF fibroblasts during myofibroblastic differentiation. These data identify the GLI transcription factors as potential therapeutic targets in lung fibrosis.
Assuntos
Diferenciação Celular , Proteínas Hedgehog/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Fator de Crescimento Transformador beta/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Cílios/efeitos dos fármacos , Cílios/patologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Hedgehog/genética , Humanos , Fibrose Pulmonar Idiopática/genética , Imuno-Histoquímica , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Miofibroblastos/efeitos dos fármacos , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Alcaloides de Veratrum/farmacologiaRESUMO
Idiopathic pulmonary fibrosis is currently believed to be driven by alveolar epithelial cells, with abnormally activated alveolar epithelial cells accumulating in an attempt to repair injured alveolar epithelium (1). Thus, targeting the alveolar epithelium to prevent or inhibit the development of pulmonary fibrosis might be an interesting therapeutic option in this disease. Hepatocyte growth factor (HGF) is a growth factor for epithelial and endothelial cells, which is secreted by different cell types, especially fibroblasts and neutrophils. HGF has mitogenic, motogenic, and morphogenic properties and exerts an antiapoptotic action on epithelial and endothelial cells. HGF has also proangiogenic effect. In vitro, HGF inhibits epithelial-to-mesenchymal cell transition and promotes myofibroblast apoptosis. In vivo, HGF has antifibrotic properties demonstrated in experimental models of lung, kidney, heart, skin, and liver fibrosis. Hence, the modulation of HGF may be an attractive target for the treatment of lung fibrosis.
Assuntos
Fator de Crescimento de Hepatócito/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Apoptose , Sobrevivência Celular , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Fibroblastos/metabolismo , Humanos , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/metabolismo , Fator de Crescimento Transformador beta/metabolismo , CicatrizaçãoRESUMO
OBJECTIVES: Fibroblast migration is an initiating step in fibroproliferation; its involvement during acute lung injury and acute respiratory distress syndrome remains poorly understood. The aims of this study were: 1) to determine whether bronchoalveolar lavage fluids from patients with acute lung injury/acute respiratory distress syndrome modulate lung fibroblast migration; 2) to assess lung fibroblast migration's clinical relevance; and 3) to evaluate the role of the platelet-derived growth factor pathway in this effect. DESIGN: Prospective cohort study. SETTING: Three intensive care units of a large tertiary referral center. PATIENTS: Ninety-three ventilated patients requiring bronchoalveolar lavage fluids were enrolled (48 with acute respiratory distress syndrome, 33 with acute lung injury, and 12 ventilated patients without acute lung injury/acute respiratory distress syndrome). INTERVENTIONS: After bronchoalveolar lavage fluids collection during standard care, the patients were followed up for 28 days and clinical outcomes were recorded. Migration assays were performed by using a Transwell model; bronchoalveolar lavage fluids platelet-derived growth factor and soluble platelet-derived growth factor receptor-α were characterized by Western blot and measured by ELISA. MEASUREMENTS AND MAIN RESULTS: Most of the bronchoalveolar lavage fluids inhibited basal fibroblast migration. Bronchoalveolar lavage fluids chemotactic index increased with severity of lung injury (28% in patients without acute lung injury/acute respiratory distress syndrome and with acute lung injury vs. 91% in acute respiratory distress syndrome patients; p = .016). In acute lung injury/acute respiratory distress syndrome patients, inhibition of basal fibroblast migration by bronchoalveolar lavage fluids below 52% was independently associated with a lower 28-day mortality (odds ratio [95% confidence interval] 0.313 [0.10-0.98], p = .046). Platelet-derived growth factor-related peptides and soluble platelet-derived growth factor-Rα were detected in all bronchoalveolar lavage fluids from acute lung injury/acute respiratory distress syndrome patients. The effect of bronchoalveolar lavage fluids stimulating migration was inhibited by a specific platelet-derived growth factor receptor inhibitor (AG1296). Bronchoalveolar lavage fluids inhibiting migration reversed the effect of rh-platelet-derived growth factor-BB and reduced by 40% the binding of 125I-platelet-derived growth factor-BB to fibroblast cell surface in favor of a role for platelet-derived growth factor-sRα. CONCLUSIONS: : Together, our results suggest that during acute lung injury, fibroblast migration is modulated by bronchoalveolar lavage fluids through a platelet-derived growth factor/platelet-derived growth factor-sRα balance. Migration is associated with clinical severity and patient 28-day mortality.
Assuntos
Lesão Pulmonar Aguda/metabolismo , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/fisiologia , Fibroblastos/fisiologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Síndrome do Desconforto Respiratório/metabolismo , Lesão Pulmonar Aguda/epidemiologia , Idoso , Western Blotting , Lavagem Broncoalveolar , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Unidades de Terapia Intensiva , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/mortalidade , Análise Multivariada , Neutrófilos/metabolismo , Estudos Prospectivos , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Respiração Artificial , Síndrome do Desconforto Respiratório/epidemiologia , Índice de Gravidade de Doença , Tirfostinas/farmacologiaRESUMO
OBJECTIVE: Fibrocytes are mesenchymal progenitors involved in normal and pathologic repair. The aims of this study were: 1) to quantify fibrocytes in bronchoalveolar lavage fluid from patients with or without acute lung injury and acute respiratory distress syndrome; and 2) to evaluate the prognostic value of bronchoalveolar lavage fibrocyte percentage in patients with acute lung injury and acute respiratory distress syndrome. DESIGN: Prospective cohort study. SETTING: Three intensive care units of a large tertiary referral center. PATIENTS: One hundred twenty-two ventilated patients requiring bronchoalveolar lavage were enrolled (62 acute respiratory distress syndrome, 30 acute lung injury, 30-ventilated patients without acute lung injury and acute respiratory distress syndrome). INTERVENTIONS: After bronchoalveolar lavage collection during standard care, the patients were followed up for 28 days and clinical outcome was recorded. Fibrocytes (CD45+/collagen 1+) were quantified in bronchoalveolar lavage by flow cytometry. Comparison of bronchoalveolar lavage fibrocyte percentage from patients with or without acute lung injury and acute respiratory distress syndrome was performed using a Wilcoxon test. A multivariate analysis using a Cox model was performed to study the independent predictors of survival. MEASUREMENTS AND MAIN RESULTS: Fibrocytes were detected in 90 of 92 (98%) bronchoalveolar lavages from patients with acute lung injury and acute respiratory distress syndrome. The median percentage of bronchoalveolar lavage fibrocytes was significantly higher in patients with acute lung injury and acute respiratory distress syndrome (5.0%) in comparison with ventilated control subjects (0.9%, p < .0001). After adjustment for age, comorbidity of malignancy, and severity of illness, a bronchoalveolar lavage fibrocyte percentage >6% was independently associated with a higher 28-day mortality in patients with acute lung injury and acute respiratory distress syndrome (hazard ratio [95% confidence interval] 6.15 [2.78-13.64], p ≤ .0001). Addition of bronchoalveolar lavage fibrocyte percentage in a clinical model predicting mortality in patients with acute lung injury and acute respiratory distress syndrome improved global fit and discriminatory capacity (c-statistic, 0.78-0.85; p = .007). CONCLUSIONS: Fibrocytes are detectable in bronchoalveolar lavage during acute lung injury and acute respiratory distress syndrome. A bronchoalveolar lavage fibrocyte percentage >6% provides an additive prognostic value to clinical predictors and may be useful to identify patients with acute lung injury and acute respiratory distress syndrome at highest risk of an adverse outcome.
Assuntos
Lesão Pulmonar Aguda/diagnóstico , Alvéolos Pulmonares/citologia , Lesão Pulmonar Aguda/patologia , Fatores Etários , Idoso , Líquido da Lavagem Broncoalveolar/citologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Alvéolos Pulmonares/patologia , Respiração Artificial , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/patologia , Resultado do TratamentoRESUMO
RATIONALE: Injury to alveolar epithelial cells is central to the pathophysiology of idiopathic pulmonary fibrosis (IPF). An abnormal autoimmune response directed against antigens of the alveolar epithelium may contribute to the disease. OBJECTIVES: To detect circulating autoantibodies (autoAbs) directed against epithelial structures. METHODS: We performed immunoblot by separating human placental amnion extract or alveolar epithelial cell (A549 cell line) proteins on polyacrylamide gels, blotting on nitrocellulose membranes, and incubating with serum from patients with IPF (n = 40) or healthy subjects (n = 40). Proteomic analysis and mass spectrometry characterized the target protein. Inhibition experiments performed with the correspondent recombinant protein confirmed our results. MEASUREMENTS AND MAIN RESULTS: We identified IgG autoAbs recognizing a 200-kD protein in the serum of patients with IPF. Proteomic analysis identified this protein as human periplakin (PPL), a component of desmosomes. Anti-PPL Abs were found by immunoblot in both serum and bronchoalveolar lavage in patients with IPF: 16/40 (40%) of them were positive versus none of the control subjects. Immunohistochemistry revealed that PPL was strongly expressed in bronchial and alveolar epithelium, but that PPL exhibited changes in intracellular localization among normal and fibrotic alveolar epithelium. In an alveolar epithelial wound repair assay, an anti-PPL IgG decreased cell migration. Recombinant PPL induced bronchoalveolar lavage T lymphocyte proliferation. Patients with IPF with anti-PPL Abs had a more severe respiratory disease, despite no difference in survival. CONCLUSIONS: We found a new circulating autoAb directed against PPL in patients with IPF, associated with a more severe disease.
Assuntos
Autoanticorpos/sangue , Autoimunidade , Fibrose Pulmonar Idiopática/imunologia , Imunoglobulina G/sangue , Plaquinas/sangue , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Fibrose Pulmonar Idiopática/sangue , Fibrose Pulmonar Idiopática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mucosa Respiratória/imunologia , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Few data concern the pathophysiology of primary spontaneous pneumothorax (PSP), which is associated with alveolar hypoxia/reoxygenation. This study tested the hypothesis that PSP is associated with oxidative stress in lung macrophages. We analysed expression of the oxidative stress marker 4-HNE; the antioxidant and anti-inflammatory proteins heme oxygenase-1 (HO-1), biliverdin reductase (BVR) and heavy chain of ferritin (H-ferritin); and the transcription factors controlling their expression Nrf2 and HIF-1alpha, in lung samples from smoker and nonsmoker patients with PSP (PSP-S and PSP-NS), cigarette smoke being a risk factor of recurrence of the disease. METHODOLOGY/PRINCIPAL FINDINGS: mRNA was assessed by RT-PCR and proteins by western blot, immunohistochemistry and confocal laser analysis. 4-HNE, HO-1, BVR and H-ferritin were increased in macrophages from PSP-S as compared to PSP-NS and controls (C). HO-1 increase was associated with increased expression of HIF-1alpha mRNA and protein in alveolar macrophages in PSP-S patients, whereas Nrf2 was not modified. To understand the regulation of HO-1, BVR and H-ferritin, THP-1 macrophages were exposed to conditions mimicking conditions in C, PSP-S and PSP-NS patients: cigarette smoke condensate (CS) or air exposure followed or not by hypoxia/reoxygenation. Silencing RNA experiments confirmed that HIF-1alpha nuclear translocation was responsible for HO-1, BVR and H-ferritin induction mediated by CS and hypoxia/reoxygenation. CONCLUSIONS/SIGNIFICANCE: PSP in smokers is associated with lung macrophage oxidative stress. The response to this condition involves HIF-1alpha-mediated induction of HO-1, BVR and H-ferritin.
Assuntos
Apoferritinas/metabolismo , Heme Oxigenase-1/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Macrófagos/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Pneumotórax/enzimologia , Fumar/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Apoferritinas/genética , Biópsia , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Hipóxia Celular , Linhagem Celular , Indução Enzimática , Proteína Básica Maior de Eosinófilos , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Pulmão/patologia , Macrófagos/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Oxigênio/metabolismo , Pneumotórax/patologia , Proteoglicanas/genética , Proteoglicanas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
RATIONALE: Lung dendritic cells (DCs) have been shown to accumulate in human fibrotic lung disease, but little is known concerning a role for DCs in the pathogenesis of fibrotic lung. OBJECTIVES: To characterize lung DCs in an in vivo model of bleomycin-induced pulmonary fibrosis in mice. METHODS: We characterized the kinetics and activation of pulmonary DCs during the course of bleomycin-induced lung injury by flow cytometry on lung single-cell suspensions. We also characterized the lymphocytes accumulating in bleomycin lung and the chemokines susceptible to favor the recruitment of immune cells. MEASUREMENTS AND MAIN RESULTS: We show, for the first time, that increased numbers of CD11c(+)/major histocompatibility complex class II(+) DCs, including CD11b(hi) monocyte-derived inflammatory DCs, infiltrate the lung of treated animals during the fibrotic phase of the response to bleomycin. These DCs are mature DCs expressing CD40, CD86, and CD83. They are associated with increased numbers of recently activated memory T cells expressing CD44, CD40L, and CD28, suggesting that fully mature DCs and Ag-experienced T cells can drive an efficient effector immune response within bleomycin lung. Most importantly, when DCs are inactivated with VAG539, a recently described new immunomodulator, VAG539 treatment attenuates the hallmarks of bleomycin lung injury. CONCLUSIONS: These findings identify lung DCs as key proinflammatory cells potentially able to sustain pulmonary inflammation and fibrosis in the bleomycin model.
Assuntos
Células Dendríticas/metabolismo , Pulmão/patologia , Fibrose Pulmonar/patologia , Animais , Antígenos CD/metabolismo , Bleomicina/farmacologia , Lavagem Broncoalveolar , Líquido da Lavagem Broncoalveolar/citologia , Quimiocinas/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Fatores Imunológicos/farmacologia , Pulmão/metabolismo , Complexo Principal de Histocompatibilidade/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Linfócitos T/metabolismoRESUMO
Sodium transport via epithelial sodium channels (ENaC) expressed in alveolar epithelial cells (AEC) provides the driving force for removal of fluid from the alveolar space. The membrane-bound channel-activating protease 1 (CAP1/Prss8) activates ENaC in vitro in various expression systems. To study the role of CAP1/Prss8 in alveolar sodium transport and lung fluid balance in vivo, we generated mice lacking CAP1/Prss8 in the alveolar epithelium using conditional Cre-loxP-mediated recombination. Deficiency of CAP1/Prss8 in AEC induced in vitro a 40% decrease in ENaC-mediated sodium currents. Sodium-driven alveolar fluid clearance (AFC) was reduced in CAP1/Prss8-deficient mice, due to a 48% decrease in amiloride-sensitive clearance, and was less sensitive to beta(2)-agonist treatment. Intra-alveolar treatment with neutrophil elastase, a soluble serine protease activating ENaC at the cell surface, fully restored basal AFC and the stimulation by beta(2)-agonists. Finally, acute volume-overload increased alveolar lining fluid volume in CAP1/Prss8-deficient mice. This study reveals that CAP1 plays a crucial role in the regulation of ENaC-mediated alveolar sodium and water transport and in mouse lung fluid balance.
Assuntos
Canais Epiteliais de Sódio/metabolismo , Água Extravascular Pulmonar/metabolismo , Pulmão/metabolismo , Alvéolos Pulmonares/metabolismo , Serina Endopeptidases/metabolismo , Equilíbrio Hidroeletrolítico , Agonistas Adrenérgicos beta/farmacologia , Animais , Células Cultivadas , Células Epiteliais/metabolismo , Canais Epiteliais de Sódio/genética , Deleção de Genes , Expressão Gênica , Camundongos , Alvéolos Pulmonares/citologia , Edema Pulmonar/metabolismo , Mucosa Respiratória/metabolismo , Serina Endopeptidases/genética , Equilíbrio Hidroeletrolítico/efeitos dos fármacosRESUMO
Hepatocyte growth factor (HGF) is a growth factor for alveolar epithelial cells. Activation of pro-HGF to HGF is regulated by the HGF activator (HGFA), a serine protease, and a specific inhibitor (HGFA inhibitor-1, HAI-1). An imbalance in the HGFA/HAI-1 system might contribute to lung fibrosis. Pro-HGF activation capacity from bronchoalveolar lavage (BAL) fluid was evaluated 3, 7, and 14 days after the intratracheal bleomycin injection (Bleo) in mice with or without thrombin. BAL fluid from naïve mice was used as control. HGFA and HAI-1 mRNA were evaluated by QPCR in the whole lung or by Western blot in BAL fluid. BAL fluid from control mice and Bleo mice activated pro-HGF in vitro at a similar degree. Thrombin accelerated proHGF activation by Bleo BAL on Day 3 and Day 7, but not on Day 14, or in control BAL. Incubation of pro-HGF with BAL from Bleo Day 3 and Day 7 mice increased phosphorylation of HGFR on A549 cells. Thrombin-induced pro-HGF activation was inhibited by an anti-HGFA antibody and accelerated by an anti-HAI-1 antibody. Active HGFA was not detected in control BAL and was strongly induced in Bleo BAL. HGFA concentrations were higher on Day 3 and Day 7 than on Day 14. HAI-1 was detected at low levels in control BAL and increased strongly by Day 3 with stable concentrations until Day 14. By demonstrating an imbalance between HGFA and HAI-1 expression in BAL fluid, our results highlight a defective thrombin-dependent proHGF activation system at the fibrotic phase of bleomycin-induced pulmonary fibrosis.
Assuntos
Bleomicina , Fator de Crescimento de Hepatócito/metabolismo , Precursores de Proteínas/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Animais , Anticorpos Neutralizantes/imunologia , Líquido da Lavagem Broncoalveolar , Linhagem Celular , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Pulmão/metabolismo , Pulmão/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas Secretadas Inibidoras de Proteinases , Proteínas Proto-Oncogênicas c-met/metabolismo , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Fibrose Pulmonar/patologia , Serina Endopeptidases/genética , Serina Endopeptidases/imunologia , Serina Endopeptidases/metabolismoRESUMO
Sarcoidosis results from an uncontrolled cell-mediated immune reaction involving activated T cells and monocytes-macrophages, characterized by the formation of typical granulomas at the sites of the lesions. The interactions between both cell types induce the release of several mediators that play a central role in the development of granulomas, allowing to design new therapies. The aetiology of sarcoidosis remains unknown, but the disease is currently viewed as the consequence of a chronic immunological response associating a genetic susceptibility and specific environmental factors.
Assuntos
Sarcoidose/fisiopatologia , Citocinas/metabolismo , Meio Ambiente , Predisposição Genética para Doença , Granuloma/fisiopatologia , Humanos , Sarcoidose/etiologiaRESUMO
Sarcoidosis is a multisystemic disorder of unknown cause characterized by the formation of immune granulomas in involved organs. It is an ubiquitous disease with incidence (varying according to age, sex, race and geographic origin) estimated at around 16.5/100,000 in men and 19/100,000 in women. The lung and the lymphatic system are predominantly affected but virtually every organ may be involved. Other severe manifestations result from cardiac, neurological, ocular, kidney or laryngeal localizations. In most cases, sarcoidosis is revealed by persistent dry cough, eye or skin manifestations, peripheral lymph nodes, fatigue, weight loss, fever or night sweats, and erythema nodosum. Abnormal metabolism of vitamin D3 within granulomatous lesions and hypercalcemia are possible. Chest radiography is abnormal in about 90% of cases and shows lymphadenopathy and/or pulmonary infiltrates (without or with fibrosis), defining sarcoidosis stages from I to IV. The etiology remains unknown but the prevailing hypothesis is that various unidentified, likely poorly degradable antigens of either infectious or environmental origin could trigger an exaggerated immune reaction in genetically susceptible hosts. Diagnosis relies on compatible clinical and radiographic manifestations, evidence of non-caseating granulomas obtained by biopsy through tracheobronchial endoscopy or at other sites, and exclusion of all other granulomatous diseases. The evolution and severity of sarcoidosis are highly variable. Mortality is estimated at between 0.5-5%. In most benign cases (spontaneous resolution within 24-36 months), no treatment is required but a regular follow-up until recovery is necessary. In more serious cases, a medical treatment has to be prescribed either initially or at some point during follow-up according to clinical manifestations and their evolution. Systemic corticosteroids are the mainstay of treatment of sarcoidosis. The minimal duration of treatment is 12 months. Some patients experience repeated relapses and may require long-term low-dose corticosteroid therapy during years. Other treatments (immunosuppressive drugs and aminoquinolins) may be useful in case of unsatisfactory response to corticosteroids, poor tolerance and as sparing agents when high doses of corticosteroids are needed for a long time. In some strictly selected cases refractory to standard therapy, specific antiTNF-alpha agents may offer precious improvement. Some patients benefit from topical corticosteroids.
Assuntos
Sarcoidose/diagnóstico , Sarcoidose/fisiopatologia , Diagnóstico Diferencial , Humanos , Sarcoidose/terapiaRESUMO
RATIONALE: There is growing evidence that resident cells, such as fibroblasts and epithelial cells, can drive the persistent accumulation of dendritic cells (DCs) in chronically inflamed tissue, leading to the organization and the maintenance of ectopic lymphoid aggregates. This phenomenon, occurring through a chemokine-mediated retention mechanism, has been documented in various disorders, but not in fibrotic interstitial lung disorders in which the presence of organized lymphoid follicles has been documented. OBJECTIVES: To characterize the distribution of DCs in fibrotic lung, and to analyze the expression of the main chemokines known to regulate DC recruitment. METHODS: Lung resection tissue (lungs with idiopathic pulmonary fibrosis; n = 12; lungs with nonspecific interstitial pneumonia, n = 5; control lungs, n = 5) was snap-frozen for subsequent immunohistochemical techniques on serial sections and reverse transcriptase-polymerase chain reaction analysis. MEASUREMENTS AND MAIN RESULTS: Results were similar in idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia lungs, which were heavily infiltrated by immature DCs in established fibrosis and in areas of epithelial hyperplasia. Altered epithelial cells and fibroblasts, particularly in fibroblastic foci, frankly expressed all chemokines (CCL19, CCL20, CCL22, and CXCL12) susceptible to favor the recruitment of immune cells. Lymphoid follicles were infiltrated by maturing DCs, which could originate from the pool of DCs accumulating in their vicinity. CONCLUSIONS: These findings suggest that resident cells in pulmonary fibrosis can sustain chronic inflammation by driving the accumulation of DCs with the potential to mature locally within ectopic lymphoid follicles. Future strategies should consider DCs or chemokines as therapeutic targets in the treatment of pulmonary fibrosis.
Assuntos
Quimiocinas CC/metabolismo , Células Dendríticas/fisiologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Adulto , Idoso , Estudos de Casos e Controles , Contagem de Células , Movimento Celular , Células Epiteliais/fisiologia , Feminino , Fibroblastos/fisiologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Despite the continuous and renewed interest in IPF, the precise biological mechanisms underlying the development of fibrosis and leading to the irreversible destruction of the lung are still unknown. Inflammation seems to play a minor role at the initiation of the disease. Identification of excessive apoptosis of alveolar epithelial cells led to the hypothesis that the disorder results from repeated alveolar epithelial cell injury and activation. In turn, alveolar epithelial cells induce the recruitment, proliferation, and activation of mesenchymal cells with the formation of fibroblastic foci and the abnormal accumulation of extracellular matrix. Fibroblastic foci are connected in a tridimensional reticulum. Circulating mesenchymal precursors called fibrocytes, and transdifferenciation of epithelial cells, endothelial cells and/or mesothelial cells, may all contribute to the accumulation of fibroblasts in the lung.
Assuntos
Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/fisiopatologia , Apoptose , Proliferação de Células , Transdiferenciação Celular , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/metabolismo , Humanos , Inflamação/fisiopatologiaRESUMO
UNLABELLED: Idiopathic pulmonary fibrosis (IPF) is characterized by an uncontrolled accumulation and activation of lung fibroblasts. A modulation of fibroblast activation has been observed in various systems with octreotide, a synthetic somatostatin analog with strong affinity for the somatostatin receptor subtype 2 (sst2). One aim of our study was to evaluate the expression of somatostatin receptors in the lungs of patients with IPF. A second aim was to evaluate the relationship between 111In-octreotide uptake and the effect of pulmonary fibrosis as assessed by lung function tests and parameters and by radiologic findings. METHODS: We investigated 11 patients with IPF, 6 patients with pulmonary fibrosis associated with systemic sclerosis (SSc), and 19 patients with disease not of the lung (control patients). The expression of somatostatin receptors was evaluated in vivo using 111In-octreotide scintigraphy. We evaluated the relationship between 111In-octreotide uptake and the activity of pulmonary fibrosis as assessed by lung function tests, bronchoalveolar lavage (BAL) cellularity, and high-resolution CT (HRCT) of the chest. Planar images and thoracic SPECT (24 h) were performed after injection of 222 MBq of 111In-octreotide. Lung uptake was quantified using the lung-to-background ratio (L/B). In addition, the expression of sst2 was evaluated in vitro, in frozen lung-tissue samples using autoradiography, and in human cultures of lung fibroblasts using a ligand-binding assay. RESULTS: Compared with lung uptake in control patients (median L/B, 1.25; range, 1.14-1.49), lung uptake was increased in all 11 IPF patients (median L/B, 2.63; range, 1.59-3.13; P < 0.001) and in 4 of 6 SSc patients (median L/B, 1.68; range, 1.42-2.16). The L/B was lower in SSc patients than in IPF patients (P = 0.011). Increased uptake correlated with the alteration of lung function (carbon monoxide diffusing capacity [rho = -0.655; P = 0.038], diffusing capacity for carbon monoxide and alveolar volume ratio [rho = -0.627; P = 0.047], vital capacity [rho = -0.609; P = 0.054], and total lung capacity [rho = -0.598; P = 0.058]) and with the intensity of alveolitis (total BAL cellularity [rho = 0.756; P = 0.045], neutrophil counts [rho = 0.738; P = 0.05]), and HRCT fibrosis score (rho = 0.673; P = 0.007). Autoradiography suggested that vascular structures were a prominent binding site. Lung fibroblasts expressed somatostatin receptors in vitro as measured by binding assay. CONCLUSION: Our preliminary results identified an increased expression of sst2 in (mainly idiopathic) pulmonary fibrosis. Lung uptake correlates with the alteration of lung function and with the intensity of alveolitis.