RESUMEN
Functional variants of the gene for the cytokine macrophage migration inhibitory factor (MIF) are defined by a 4-nucleotide promoter microsatellite (-794 CATT5-8, rs5844572) and confer risk for autoimmune, infectious, and oncologic diseases. We describe herein the discovery of a prototypic, small molecule inhibitor of MIF transcription with selectivity for high microsatellite repeat number and correspondingly high gene expression. Utilizing a high-throughput luminescent proximity screen, we identify 1-carbomethoxy-5-formyl-4,6,8-trihydroxyphenazine (CMFT) to inhibit the functional interaction between the transcription factor ICBP90 (namely, UHRF1) and the MIF -794 CATT5-8 promoter microsatellite. CMFT inhibits MIF mRNA expression in a -794 CATT5-8 length-dependent manner with an IC50 of 470 nM, and preferentially reduces ICBP90-dependent MIF mRNA and protein expression in high-genotypic versus low-genotypic MIF-expressing macrophages. RNA expression analysis also showed CMFT to downregulate MIF-dependent, inflammatory gene expression with little evidence of off-target metabolic toxicity. These findings provide proof-of-concept for advancing the pharmacogenomic development of precision-based MIF inhibitors for diverse autoimmune and inflammatory conditions.
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BACKGROUND: Trained immunity results in long-term immunological memory, provoking a faster and greater immune response when innate immune cells encounter a secondary, often heterologous, stimulus. We have previously shown that house dust mite (HDM)-induced innate training is amplified in mice expressing the human macrophage migration inhibitory factor (MIF) CATT7 functional polymorphism. AIM: This study investigated the ability of mesenchymal stromal cells (MSCs) to modulate MIF-driven trained immunity both in vitro and in vivo. METHODS: Compared with wild-type mice, in vivo HDM-primed bone marrow-derived macrophages (BMDMs) from CATT7 mice expressed significantly higher levels of M1-associated genes following lipopolysaccharide stimulation ex vivo. Co-cultures of CATT7 BMDMs with MSCs suppressed this HDM-primed effect, with tumor necrosis factor alpha (TNF-α) being significantly decreased in a cyclooxygenase 2 (COX-2)-dependent manner. Interestingly, interleukin 6 (IL-6) was suppressed by MSCs independently of COX-2. In an in vitro training assay, MSCs significantly abrogated the enhanced production of pro-inflammatory cytokines by HDM-trained CATT7 BMDMs when co-cultured at the time of HDM stimulus on day 0, displaying their therapeutic efficacy in modulating an overzealous human MIF-dependent immune response. Utilizing an in vivo model of HDM-induced trained immunity, MSCs administered systemically on day 10 and day 11 suppressed this trained phenomenon by significantly reducing TNF-α and reducing IL-6 and C-C motif chemokine ligand 17 (CCL17) production. CONCLUSIONS: This novel study elucidates how MSCs can attenuate an MIF-driven, HDM-trained response in CATT7 mice in a model of allergic airway inflammation.
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High level expression of the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) has been associated with severe asthma. The role of MIF and its functional promotor polymorphism in innate immune training is currently unknown. Using novel humanized CATT7 MIF mice, this study is the first to investigate the effect of MIF on bone marrow-derived macrophage (BMDM) memory after house dust mite (HDM) challenge. CATT7 BMDMs demonstrated a significant primed increase in M1 markers following HDM and LPS stimulation, compared to naive mice. This M1 signature was found to be MIF-dependent, as administration of a small molecule MIF inhibitor, SCD-19, blocked the induction of this pro-inflammatory M1-like phenotype in BMDMs from CATT7 mice challenged with HDM. Training naive BMDMs in vitro with HDM for 24 h followed by a rest period and subsequent stimulation with LPS led to significantly increased production of the pro-inflammatory cytokine TNFα in BMDMs from CATT7 mice but not WT mice. Addition of the pan methyltransferase inhibitor MTA before HDM training significantly abrogated this effect in BMDMs from CATT7 mice, suggesting that HDM-induced training is associated with epigenetic remodelling. These findings suggest that trained immunity induced by HDM is under genetic control, playing an important role in asthma patients with the high MIF genotypes (CATT6/7/8).
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Asma , Factores Inhibidores de la Migración de Macrófagos , Humanos , Animales , Ratones , Factores Inhibidores de la Migración de Macrófagos/genética , Lipopolisacáridos/toxicidad , Pyroglyphidae , Asma/genética , Inflamación , Oxidorreductasas Intramoleculares/genéticaRESUMEN
Current asthma therapies focus on reducing symptoms but fail to restore existing structural damage. Mesenchymal stromal cell (MSC) administration can ameliorate airway inflammation and reverse airway remodeling. However, differences in patient disease microenvironments seem to influence MSC therapeutic effects. A polymorphic CATT tetranucleotide repeat at position 794 of the human macrophage migration inhibitory factor (hMIF) gene has been associated with increased susceptibility to and severity of asthma. We investigated the efficacy of human MSCs in high- vs. low-hMIF environments and the impact of MIF pre-licensing of MSCs using humanized MIF mice in a clinically relevant house dust mite (HDM) model of allergic asthma. MSCs significantly attenuated airway inflammation and airway remodeling in high-MIF-expressing CATT7 mice but not in CATT5 or wild-type littermates. Differences in efficacy were correlated with increased MSC retention in the lungs of CATT7 mice. MIF licensing potentiated MSC anti-inflammatory effects at a previously ineffective dose. Mechanistically, MIF binding to CD74 expressed on MSCs leads to upregulation of cyclooxygenase 2 (COX-2) expression. Blockade of CD74 or COX-2 function in MSCs prior to administration attenuated the efficacy of MIF-licensed MSCs in vivo. These findings suggest that MSC administration may be more efficacious in severe asthma patients with high MIF genotypes (CATT6/7/8).
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Asma , Factores Inhibidores de la Migración de Macrófagos , Células Madre Mesenquimatosas , Animales , Humanos , Ratones , Remodelación de las Vías Aéreas (Respiratorias) , Asma/terapia , Ciclooxigenasa 2/genética , Inflamación/metabolismo , Factores Inhibidores de la Migración de Macrófagos/genética , Células Madre Mesenquimatosas/metabolismoRESUMEN
Macrophage migration inhibitory factor (MIF) expression is controlled by a functional promoter polymorphism, where the number of tetranucleotide repeats (CATTn ) corresponds to the level of MIF expression. To examine the role of this polymorphism in a pre-clinical model of allergic asthma, novel humanized MIF mice with increasing CATT repeats (CATT5 and CATT7 ) were used to generate a physiologically relevant scale of airway inflammation following house dust mite (HDM) challenge. CATT7 mice expressing high levels of human MIF developed an aggressive asthma phenotype following HDM challenge with significantly elevated levels of immune cell infiltration, production of inflammatory mediators, goblet cell hyperplasia, subepithelial collagen deposition, and airway resistance compared to wild-type controls. Importantly the potent MIF inhibitor SCD-19 significantly mitigated the pathophysiology observed in CATT7 mice after HDM challenge, demonstrating the fundamental role of endogenous human MIF expression in the severity of airway inflammation in vivo. Up to now, there are limited reproducible in vivo models of asthma airway remodeling. Current asthma medications are focused on reducing the acute inflammatory response but have limited effects on airway remodeling. Here, we present a reproducible pre-clinical model that capitulates asthma airway remodeling and suggests that in addition to having pro-inflammatory effects MIF may play a role in driving airway remodeling.
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Asma , Factores Inhibidores de la Migración de Macrófagos , Humanos , Animales , Ratones , Pyroglyphidae , Factores Inhibidores de la Migración de Macrófagos/genética , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Remodelación de las Vías Aéreas (Respiratorias) , Pulmón/metabolismo , Inflamación/metabolismo , Modelos Animales de Enfermedad , Oxidorreductasas Intramoleculares/genética , Oxidorreductasas Intramoleculares/metabolismoRESUMEN
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial pneumonia of unknown aetiology with a mean survival rate of less than 3 years. No previous studies have been performed on the role of co-infection (viral and bacterial infection) in the pathogenesis and progression of IPF. In this study, we investigated the role of viral/bacterial infection and coinfection and their possible association with pathogenesis and progression of IPF. METHODS: We investigated the prevalence and impact of bacterial and viral coinfection in IPF patients (n = 67) in the context of pulmonary function (FVC, FEV1 and DLCO), disease status and mortality risk. Using principal component analysis (PCA), we also investigated the relationship between distribution of bacterial and viral co-infection in the IPF cohort. RESULTS: Of the 67 samples, 17.9% samples were positive for viral infection, 10.4% samples were positive for bacterial infection and 59.7% samples were positive coinfection. We demonstrated that IPF patients who were co-infected had a significantly increased risk of mortality compared (p = 0.031) with IPF patients who were non-infected [Hazard ratio: 8.12; 95% CI 1.3-26.9]. CONCLUSION: In this study, we report for the first time that IPF patients who were coinfected with bacterial and viral infection have significantly decreased FVC and DLCO (% predicted). Besides, the results demonstrated the increased AE-IPF, increased incidence of death and risk of mortality in infected/coinfected patients compared to non-infected IPF patients.
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Infecciones Bacterianas/epidemiología , Fibrosis Pulmonar Idiopática/microbiología , Fibrosis Pulmonar Idiopática/virología , Virosis/epidemiología , Anciano , Infecciones Bacterianas/complicaciones , Coinfección/mortalidad , Progresión de la Enfermedad , Femenino , Humanos , Fibrosis Pulmonar Idiopática/mortalidad , Masculino , Persona de Mediana Edad , Prevalencia , Tasa de Supervivencia , Virosis/complicacionesRESUMEN
Rationale: The Toll-like receptor 3 Leu412Phe (TLR3 L412F) polymorphism attenuates cellular antiviral responses and is associated with accelerated disease progression in idiopathic pulmonary fibrosis (IPF). The role of TLR3 L412F in bacterial infection in IPF or in acute exacerbations (AE) has not been reported. Objectives: To characterize the association between TLR3 L412F and AE-related death in IPF. To determine the effect of TLR3 L412F on the lung microbiome and on antibacterial TLR responses of primary lung fibroblasts from patients with IPF. Methods: TLR-mediated antibacterial and antiviral responses were quantitated in L412F wild-type and 412F-heterozygous primary lung fibroblasts from patients with IPF using ELISA, Western blot analysis, and quantitative PCR. Hierarchical heatmap analysis was employed to establish bacterial and viral clustering in nasopharyngeal lavage samples from patients with AE-IPF. 16S ribosomal RNA quantitative PCR and pyrosequencing were used to determine the effect of TLR3 L412F on the IPF lung microbiome. Measurements and Main Results: A significant increase in AE-related death in patients with 412F-variant IPF was reported. We established that 412F-heterozygous IPF lung fibroblasts have reduced antibacterial TLR responses to LPS (TLR4), Pam3CYSK4 (TLR1/2), flagellin (TLR5), and FSL-1 (TLR6/1) and have reduced responses to live Pseudomonas aeruginosa infection. Using 16S ribosomal RNA sequencing, we demonstrated that 412F-heterozygous patients with IPF have a dysregulated lung microbiome with increased frequencies of Streptococcus and Staphylococcus spp. Conclusions: This study reveals that TLR3 L412F dysregulates the IPF lung microbiome and reduces the responses of IPF lung fibroblasts to bacterial TLR agonists and live bacterial infection. These findings identify a candidate role for TLR3 L412F in viral- and bacterial-mediated AE death.
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Fibrosis Pulmonar Idiopática , Receptor Toll-Like 3/genética , Antibacterianos , Antivirales , Progresión de la Enfermedad , Humanos , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/microbiología , ARN Ribosómico 16SRESUMEN
The aim of this project was to identify candidate novel therapeutic targets to facilitate the treatment of COPD using machine-based learning (ML) algorithms and penalized regression models. In this study, 59 healthy smokers, 53 healthy non-smokers and 21 COPD smokers (9 GOLD stage I and 12 GOLD stage II) were included (n = 133). 20,097 probes were generated from a small airway epithelium (SAE) microarray dataset obtained from these subjects previously. Subsequently, the association between gene expression levels and smoking and COPD, respectively, was assessed using: AdaBoost Classification Trees, Decision Tree, Gradient Boosting Machines, Naive Bayes, Neural Network, Random Forest, Support Vector Machine and adaptive LASSO, Elastic-Net, and Ridge logistic regression analyses. Using this methodology, we identified 44 candidate genes, 27 of these genes had been previously been reported as important factors in the pathogenesis of COPD or regulation of lung function. Here, we also identified 17 genes, which have not been previously identified to be associated with the pathogenesis of COPD or the regulation of lung function. The most significantly regulated of these genes included: PRKAR2B, GAD1, LINC00930 and SLITRK6. These novel genes may provide the basis for the future development of novel therapeutics in COPD and its associated morbidities.
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Algoritmos , Células Epiteliales/metabolismo , Pulmón/patología , Aprendizaje Automático , Enfermedad Pulmonar Obstructiva Crónica/genética , Adulto , Estudios de Casos y Controles , Análisis por Conglomerados , Progresión de la Enfermedad , Femenino , Regulación de la Expresión Génica , Estudios de Asociación Genética , Humanos , Masculino , Persona de Mediana Edad , Fumadores , Estadísticas no ParamétricasRESUMEN
Macrophage migration inhibitory factor (MIF) is a key proinflammatory mediator that we have previously shown to be associated with an aggressive clinical phenotype in cystic fibrosis. It possesses unique tautomerase enzymatic activity. However, to date, no human-derived substrate has been identified that has the capacity to interact with this cytokine's unique tautomerase activity. This led us to hypothesize that MIF may have the capacity to interact with external substrates. We describe for the first time how Pseudomonas aeruginosa can utilize human recombinant MIF (rMIF) to significantly (P < 0.01) enhance its endogenous biofilm formation. Our in vivo studies demonstrate that utilizing a small-molecular-weight inhibitor targeting MIF's tautomerase activity (SCD-19) significantly reduces the inflammatory response in a murine pulmonary chronic P. aeruginosa model. In addition, we show that in in vitro experiments, pretreatment of P. aeruginosa with rMIF is associated with reduced bacterial killing by tobramycin. Our novel findings support the concept of an anti-MIF strategy that targets this enzymatic activity as a potential future antibacterial therapeutic approach.-Tynan, A., Mawhinney, L., Armstrong, M. E., O'Reilly, C., Kennedy, S., Caraher, E., Jülicher, K., O'Dwyer, D., Maher, L., Schaffer, K., Fabre, A., McKone, E. F., Leng, L., Bucala, R., Bernhagen, J., Cooke, G., Donnelly, S. C. Macrophage migration inhibitory factor enhances Pseudomonas aeruginosa biofilm formation, potentially contributing to cystic fibrosis pathogenesis.
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Fibrosis Quística/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Pseudomonas aeruginosa/fisiología , Animales , Biopelículas/crecimiento & desarrollo , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/microbiología , Modelos Animales de Enfermedad , Oxidorreductasas Intramoleculares/farmacología , Factores Inhibidores de la Migración de Macrófagos/farmacología , Ratones , Proteínas Recombinantes/farmacología , Tobramicina/farmacologíaRESUMEN
The cytokine macrophage migration inhibitory factor (MIF) possesses unique tautomerase enzymatic activity, which contributes to the biological functional activity of MIF. In this study, we investigated the effects of blocking the hydrophobic active site of the tautomerase activity of MIF in the pathogenesis of lung cancer. To address this, we initially established a Lewis lung carcinoma (LLC) murine model in Mif-KO and wild-type (WT) mice and compared tumor growth in a knock-in mouse model expressing a mutant MIF lacking enzymatic activity (Mif (P1G)). Primary tumor growth was significantly attenuated in both Mif-KO and Mif (P1G) mice compared with WT mice. We subsequently undertook a structure-based, virtual screen to identify putative small molecular weight inhibitors specific for the tautomerase enzymatic active site of MIF. From primary and secondary screens, the inhibitor SCD-19 was identified, which significantly attenuated the tautomerase enzymatic activity of MIF in vitro and in biological functional screens. In the LLC murine model, SCD-19, given intraperitoneally at the time of tumor inoculation, was found to significantly reduce primary tumor volume by 90% (p < 0.001) compared with the control treatment. To better replicate the human disease scenario, SCD-19 was given when the tumor was palpable (at d 7 after tumor inoculation) and, again, treatment was found to significantly reduce tumor volume by 81% (p < 0.001) compared with the control treatment. In this report, we identify a novel inhibitor that blocks the hydrophobic pocket of MIF, which houses its specific tautomerase enzymatic activity, and demonstrate that targeting this unique active site significantly attenuates lung cancer growth in in vitro and in vivo systems.
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Antineoplásicos/uso terapéutico , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Isocumarinas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Factores Inhibidores de la Migración de Macrófagos/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patología , Línea Celular , Dinoprostona/metabolismo , Femenino , Oxidorreductasas Intramoleculares/genética , Oxidorreductasas Intramoleculares/metabolismo , Isocumarinas/farmacología , Lipopolisacáridos , Pulmón/efectos de los fármacos , Pulmón/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Factores Inhibidores de la Migración de Macrófagos/genética , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Carga Tumoral/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a disease of the lung parenchyma that is invariably fatal with a median survival of 2 - 3 years. Despite considerable progress in defining the natural history of the disease, many features of IPF pathogenesis remain poorly understood. Several recent studies have highlighted links between pattern recognition receptors of innate immunity termed 'Toll-like receptors' (TLRs) and the aberrant fibrogenesis that characterizes IPF. AREAS COVERED: In this paper, we discuss the natural history of IPF and the identification of several distinct clinical phenotypes in recent years. TLRs are receptors that recognize pathogen- and/or danger-associated molecular patterns and promote an appropriate immune response. We describe in detail some of the recent works linking defective TLR3 function and an aggressive phenotype in IPF and explore the mechanisms and potential clinical implications of this initial observation. EXPERT OPINION: We explore the potential role of TLRs in this setting. We discuss recent genetic studies and the implications for future research. We propose a model of dysregulated innate immune recognition and aberrant lung healing. The potential role of research in aiding the design of clinical trials and the evidence for targeting defective TLR3 function in IPF is presented.
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Fibrosis Pulmonar Idiopática/terapia , Terapia Molecular Dirigida , Receptor Toll-Like 3/metabolismo , Animales , Ensayos Clínicos como Asunto/métodos , Humanos , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/fisiopatología , Inmunidad Innata , FenotipoRESUMEN
Disease conditions associated with pulmonary fibrosis are progressive and have a poor long-term prognosis with irreversible changes in airway architecture leading to marked morbidity and mortalities. Using murine models we demonstrate a role for interleukin (IL)-25 in the generation of pulmonary fibrosis. Mechanistically, we identify IL-13 release from type 2 innate lymphoid cells (ILC2) as sufficient to drive collagen deposition in the lungs of challenged mice and suggest this as a potential mechanism through which IL-25 is acting. Additionally, we demonstrate that in human idiopathic pulmonary fibrosis there is increased pulmonary expression of IL-25 and also observe a population ILC2 in the lungs of idiopathic pulmonary fibrosis patients. Collectively, we present an innate mechanism for the generation of pulmonary fibrosis, via IL-25 and ILC2, that occurs independently of T-cell-mediated antigen-specific immune responses. These results suggest the potential of therapeutically targeting IL-25 and ILC2 for the treatment of human fibrotic diseases.
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Regulación de la Expresión Génica , Interleucina-17/metabolismo , Interleucinas/metabolismo , Linfocitos/citología , Fibrosis Pulmonar/metabolismo , Anciano , Animales , Moléculas de Adhesión Celular/metabolismo , Colágeno/química , Colágeno/metabolismo , Femenino , Humanos , Fibrosis Pulmonar Idiopática/patología , Inmunidad Innata , Inflamación , Interleucina-13/metabolismo , Hígado/parasitología , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Persona de Mediana Edad , Fibrosis Pulmonar/patología , Schistosoma mansoniRESUMEN
RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a fatal progressive interstitial pneumonia. The innate immune system provides a crucial function in the recognition of tissue injury and infection. Toll-like receptor 3 (TLR3) is an innate immune system receptor. We investigated the role of a functional TLR3 single-nucleotide polymorphism in IPF. OBJECTIVES: To characterize the effects of the TLR3 Leu412Phe polymorphism in primary pulmonary fibroblasts from patients with IPF and disease progression in two independent IPF patient cohorts. To investigate the role of TLR3 in a murine model of pulmonary fibrosis. METHODS: TLR3-mediated cytokine, type 1 IFN, and fibroproliferative responses were examined in TLR3 wild-type (Leu/Leu), heterozygote (Leu/Phe), and homozygote (Phe/Phe) primary IPF pulmonary fibroblasts by ELISA, real-time polymerase chain reaction, and proliferation assays. A murine model of bleomycin-induced pulmonary fibrosis was used in TLR3 wild-type (tlr3(+/+)) and TLR3 knockout mice (tlr3(-/-)). A genotyping approach was used to investigate the role of the TLR3 L412F polymorphism in disease progression in IPF using survival analysis and longitudinal decline in FVC. MEASUREMENTS AND MAIN RESULTS: Activation of TLR3 in primary lung fibroblasts from TLR3 L412F-variant patients with IPF resulted in defective cytokine, type I IFN, and fibroproliferative responses. We demonstrate increased collagen and profibrotic cytokines in TLR3 knockout mice (tlr3(-/-)) compared with wild-type mice (tlr3(+/+)). TLR3 L412F was also associated with a significantly greater risk of mortality and an accelerated decline in FVC in patients with IPF. CONCLUSIONS: This study reveals the crucial role of defective TLR3 function in promoting progressive IPF.
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Progresión de la Enfermedad , Fibrosis Pulmonar Idiopática/genética , Polimorfismo de Nucleótido Simple , Receptor Toll-Like 3/genética , Anciano , Anciano de 80 o más Años , Animales , Biomarcadores/metabolismo , Estudios de Cohortes , Ensayo de Inmunoadsorción Enzimática , Femenino , Marcadores Genéticos , Genotipo , Técnicas de Genotipaje , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/mortalidad , Fibrosis Pulmonar Idiopática/patología , Interferón Tipo I/metabolismo , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Supervivencia , Receptor Toll-Like 3/deficiencia , Receptor Toll-Like 3/metabolismoRESUMEN
Rheumatoid Arthritis (RA) is the most common Connective Tissue Disease (CTD) and represents an increasing burden on global health resources. Interstitial lung disease (ILD) has been recognised as a complication of RA but its potential for mortality and morbidity has arguably been under appreciated for decades. New studies have underscored a significant lifetime risk of ILD development in RA. Contemporary work has identified an increased risk of mortality associated with the Usual Interstitial Pneumonia (UIP) pattern which shares similarity with the most devastating of the interstitial pulmonary diseases, namely Idiopathic Pulmonary Fibrosis (IPF). In this paper, we discuss recent studies highlighting the associated increase in mortality in RA-UIP. We explore associations between radiological and histopathological features of RA-ILD and the prognostic implications of same. We emphasise the need for translational research in this area given the growing burden of RA-ILD. We highlight the importance of the respiratory physician as a key stakeholder in the multidisciplinary management of this disorder. RA-ILD focused research offers the opportunity to identify early asymptomatic disease and define the natural history of this extra articular manifestation. This may provide a unique opportunity to define key regulatory fibrotic events driving progressive disease. We also discuss some of the more challenging and novel aspects of therapy for RA-ILD.
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Artritis Reumatoide/complicaciones , Artritis Reumatoide/mortalidad , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/mortalidad , Artritis Reumatoide/terapia , Humanos , Enfermedades Pulmonares Intersticiales/terapia , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/mortalidad , Fibrosis Pulmonar/terapia , Factores de RiesgoRESUMEN
Hypertension, a key risk factor for stroke, cardiovascular disease and dementia, is associated with chronic vascular inflammation, and although poorly understood, putative mechanisms include pro-inflammatory responses induced by mechanical stretching, with cytokine release and associated up-regulated expression of adhesion molecules. Because blood pressure increases with age, we measured baseline and tumour necrosis alpha (TNF-α)-stimulated CD11b/CD18 adhesion molecule expression on leucocytes to assess any association between the two. In 38 subjects (mean age 85 years), consecutively enrolled from Belfast Elderly Longitudinal Free-Living Aging Study (BELFAST), baseline and TNF-α-stimulated CD11b/CD18 expression on separated monocytes and neutrophils increased with systolic blood pressure >120 mmHg (p = 0.05) and for lymphocytes, with diastolic blood pressure >80 mmHg (p < 0.05).These findings show increased potential stickiness of intravascular cells with increasing blood pressure which is accentuated by TNF-α, and suggest mechanistic reasons why better hypertension control is important.
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Envejecimiento/fisiología , Determinación de la Presión Sanguínea/normas , Presión Sanguínea/fisiología , Antígeno CD11b/biosíntesis , Hipertensión/fisiopatología , Leucocitos/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia Arriba/efectos de los fármacos , Anciano de 80 o más Años , Adhesión Celular/efectos de los fármacos , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión/sangre , MasculinoRESUMEN
RATIONALE: Macrophage migration inhibitory factor (MIF) is a proinflammatory mediator with unique tautomerase enzymatic activity; the precise function has not been clearly defined. We previously demonstrated that individual patients with cystic fibrosis (CF) who are genetically predisposed to be high MIF producers develop accelerated end-organ injury. OBJECTIVES: To characterize the effects of the MIF-CATT polymorphism in patients with CF ex vivo. To investigate the role of MIF's tautomerase activity in a murine model of Pseudomonas aeruginosa infection. METHODS: MIF and tumor necrosis factor (TNF)-α protein levels were assessed in plasma or peripheral blood mononuclear cell (PBMC) supernatants by ELISA. A murine pulmonary model of chronic Pseudomonas infection was used in MIF wild-type mice (mif(+/+)) and in tautomerase-null, MIF gene knockin mice (mif (P1G/P1G)). MEASUREMENTS AND MAIN RESULTS: MIF protein was measured in plasma and PBMCs from 5- and 6-CATT patients with CF; LPS-induced TNF-α production from PBMCs was also assessed. The effect of a specific inhibitor of MIF-tautomerase activity, ISO-1, was investigated in PBMCs. In the murine infection model, total weight loss, differential cell counts, bacterial load, and intraacinar airspace/tissue volume were measured. MIF and TNF-α levels were increased in 6-CATT compared with 5-CATT patients with CF. LPS-induced TNF-α production from PBMCs was attenuated in the presence of ISO-1. In a murine model of Pseudomonas infection, significantly less pulmonary inflammation and bacterial load was observed in mif(P1G/P1G) compared with mif(+/+) mice. CONCLUSIONS: MIF-tautomerase activity may provide a novel therapeutic target in patients with chronic inflammatory diseases such as CF, particularly those patients who are genetically predisposed to produce increased levels of this cytokine.
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Fibrosis Quística/enzimología , Factores Inhibidores de la Migración de Macrófagos/fisiología , Adulto , Alelos , Animales , Fibrosis Quística/sangre , Fibrosis Quística/etiología , Fibrosis Quística/genética , Femenino , Técnicas de Sustitución del Gen , Humanos , Factores Inhibidores de la Migración de Macrófagos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Neumonía/sangre , Neumonía/enzimología , Neumonía/etiología , Polimorfismo Genético , Infecciones por Pseudomonas/inmunología , Reacción en Cadena en Tiempo Real de la Polimerasa , Secuencias Repetitivas de Ácidos Nucleicos/genética , Infecciones del Sistema Respiratorio/inmunología , Estudios Retrospectivos , Factor de Necrosis Tumoral alfa/sangreRESUMEN
Macrophage migration inhibitory factor represents a key cytokine in human diseases. It plays an important role in both innate and acquired immunity and has been shown to be a key mediator of inflammatory diseases. More recently MIF has been implicated in cancer pathogenesis. Over the decades its structure and functions have been elucidated and this has led to it being further classified as a hormone and an enzyme. It has isomerase enzymatic activity and increasing evidence implicates this activity in inflammatory disease. Consequently, there is increasing interest in developing small molecular weight inhibitors which could target this novel enzymatic activity in disease. (c) 2009 International Union of Biochemistry and Molecular Biology, Inc.
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Inflamación/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Animales , Activación Enzimática , Humanos , Inflamación/genética , Factores Inhibidores de la Migración de Macrófagos/química , Factores Inhibidores de la Migración de Macrófagos/genética , Neoplasias/genética , Neoplasias/metabolismoRESUMEN
Small interfering RNAs (siRNAs) represent a novel tool to induce gene silencing in mammalian cells and clinical trials are currently ongoing to assess the therapeutic efficacy of siRNAs in various human diseases, including age-related macular degeneration and respiratory syncytial virus infection. However, previously reported off-target, nonspecific effects of siRNAs, including activation of type I IFNs and proinflammatory cytokines, remain an outstanding concern regarding use of these agents in vivo. Macrophage-migration inhibitory factor (MIF) is a pleiotropic cytokine with well-described roles in cell proliferation, tumorigenesis, and angiogenesis and represents a target gene for siRNA-based therapy in the treatment of breast cancer. However, in this study we describe an increase in MIF production from mammary adenocarcinoma (MCF-7) cells following transfection with MIF siRNA and various control siRNAs. This effect was shown to be dose-dependent and was attenuated in the presence of a double-stranded RNA-dependent protein kinase inhibitor, 2-aminopurine. Furthermore, treatment of MCF-7 cells with poly(I:C) also stimulated a PKR-dependent increase in MIF production from MCF-7 cells. The biological consequence of the siRNA-induced increase in MIF production from MCF-7 cells was a PKR-dependent increase in proliferation of breast cancer cells. Furthermore, in cDNAs prepared from a primary human breast cancer cohort, we demonstrated a significant correlation (Spearman rank correlation coefficient, r = 0.50, p < 0.0001, n = 63) between PKR- and MIF-mRNA expression. In conclusion, this study highlights the potential biological consequences of off-target, nonspecific effects of siRNAs and underlines the safety concerns regarding the use of siRNAs in the treatment of human diseases, such as cancer.
Asunto(s)
Neoplasias de la Mama/metabolismo , Factores Inhibidores de la Migración de Macrófagos/biosíntesis , ARN Bicatenario/metabolismo , ARN Interferente Pequeño/farmacología , eIF-2 Quinasa/metabolismo , 2-Aminopurina/farmacología , Neoplasias de la Mama/inmunología , Línea Celular Tumoral , Proliferación Celular , Humanos , Interferón beta/inmunología , Interferón beta/metabolismo , Factores Inhibidores de la Migración de Macrófagos/genética , Factores Inhibidores de la Migración de Macrófagos/inmunología , Poli I-C/genética , Poli I-C/farmacología , Interferencia de ARN , ARN Bicatenario/inmunología , ARN Interferente Pequeño/inmunología , ARN Interferente Pequeño/metabolismo , Transfección , eIF-2 Quinasa/antagonistas & inhibidoresRESUMEN
Similarity in structure and sequence homology has led to the identification of new members of the interleukin-1 (IL-1) ligand and receptor superfamilies. IL-1F6, IL-1F8 and IL-1F9 have been shown to signal through IL-1R-related protein 2 and IL-1 receptor accessory protein leading to activation of NFkappaB, while IL-1F7 and IL-1F10 interact with the IL-18 receptor and the soluble IL-1 receptor type I respectively. In contrast, identification of a biological role for IL-1F5 has remained elusive, with conflicting data relating to its possible ability to antagonize IL-1F9-stimulated activation of NFkappaB in Jurkat cells transfected with IL-1R-related protein 2. In this study, we set out to investigate a possible role for IL-1F5 in the brain and report that it antagonizes the inflammatory effects of IL-1beta and lipopolysaccharide (LPS) in vivo and in vitro including the inhibitory effect on long-term potentiation (LTP) in rat hippocampus. We demonstrate that IL-1F5 induces IL-4 mRNA and protein expression in glia in vitro and enhances hippocampal expression of IL-4 following intracerebroventricular (i.c.v.) injection. The inhibitory effect of IL-1F5 on LPS-induced IL-1beta is attenuated in cells from IL-4-defective (IL-4-/- mice). Our findings suggest that IL-1F5 mediates anti-inflammatory effects through its ability to induce IL-4 production and that this is a consequence of its interaction with the orphan receptor, single Ig IL-1R-related molecule (SIGIRR)/TIR8, as the effects were not observed in SIGIRR-/- mice. In contrast to its effects in brain tissue, IL-1F5 did not attenuate LPS-induced changes, or up-regulated IL-4 in macrophages or dendritic cells, suggesting that the effect is confined to the brain.