Magnus Sköld

Macitentan for the treatment of idiopathic pulmonary fibrosis: the randomised controlled MUSIC trial

Idiopathic pulmonary fibrosis is a progressive, fatal disease. This prospective, randomised, double-blind, multicentre, parallel-group, placebo-controlled phase II trial (NCT00903331) investigated the efficacy and safety of the endothelin receptor antagonist macitentan in idiopathic pulmonary fibrosis. Eligible subjects were adults with idiopathic pulmonary fibrosis of <3 years duration and a histological pattern of usual interstitial pneumonia on surgical lung biopsy. The primary objective was to demonstrate that macitentan (10 mg once daily) positively affected forced vital capacity versus placebo. Using a centralised system, 178 subjects were randomised (2:1) to macitentan (n=119) or placebo (n=59). The median change from baseline up to month 12 in forced vital capacity was -0.20 L in the macitentan arm and -0.20 L in the placebo arm. Overall, no differences between treatments were observed in pulmonary function tests or time to disease worsening or death. Median exposures to macitentan and placebo were 14.5 months and 15.0 months, respectively. Alanine and/or aspartate aminotransferase elevations over three times upper limit of normal arose in 3.4% of macitentan-treated subjects and 5.1% of placebo recipients. In conclusion, the primary objective was not met. Long-term exposure to macitentan was well tolerated with a similar, low incidence of elevated hepatic aminotransferases in each treatment group. Long-term exposure to macitentan was well tolerated in IPF in a trial that did not meet its primary end-point http://ow.ly/p0RDL

Asthmatics Exhibit Altered Oxylipin Profiles Compared to Healthy Individuals after Subway Air Exposure

Background Asthma is a chronic inflammatory lung disease that causes significant morbidity and mortality worldwide. Air pollutants such as particulate matter (PM) and oxidants are important factors in causing exacerbations in asthmatics, and the source and composition of pollutants greatly affects pathological implications. Objectives This randomized crossover study investigated responses of the respiratory system to Stockholm subway air in asthmatics and healthy individuals. Eicosanoids and other oxylipins were quantified in the distal lung to provide a measure of shifts in lipid mediators in association with exposure to subway air relative to ambient air. Methods Sixty-four oxylipins representing the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (CYP) metabolic pathways were screened using liquid chromatography-tandem mass spectrometry (LC-MS/MS) of bronchoalveolar lavage (BAL)-fluid. Validations through immunocytochemistry staining of BAL-cells were performed for 15-LOX-1, COX-1, COX-2 and peroxisome proliferator-activated receptor gamma (PPARγ). Multivariate statistics were employed to interrogate acquired oxylipin and immunocytochemistry data in combination with patient clinical information. Results Asthmatics and healthy individuals exhibited divergent oxylipin profiles following exposure to ambient and subway air. Significant changes were observed in 8 metabolites of linoleic- and α-linolenic acid synthesized via the 15-LOX pathway, and of the COX product prostaglandin E2 (PGE2). Oxylipin levels were increased in healthy individuals following exposure to subway air, whereas asthmatics evidenced decreases or no change. Conclusions Several of the altered oxylipins have known or suspected bronchoprotective or anti-inflammatory effects, suggesting a possible reduced anti-inflammatory response in asthmatics following exposure to subway air. These observations may have ramifications for sensitive subpopulations in urban areas.

The lung microbiota in early rheumatoid arthritis and autoimmunity

BackgroundAirway abnormalities and lung tissue citrullination are found in both rheumatoid arthritis (RA) patients and individuals at-risk for disease development. This suggests the possibility that the lung could be a site of autoimmunity generation in RA, perhaps in response to microbiota changes. We therefore sought to test whether the RA lung microbiome contains distinct taxonomic features associated with local and/or systemic autoimmunity.Methods16S rRNA gene high-throughput sequencing was utilized to compare the bacterial community composition of bronchoalveolar lavage fluid (BAL) in patients with early, disease-modifying anti-rheumatic drugs (DMARD)-naïve RA, patients with lung sarcoidosis, and healthy control subjects. Samples were further assessed for the presence and levels of anti-citrullinated peptide antibodies (including fine specificities) in both BAL and serum.ResultsThe BAL microbiota of RA patients was significantly less diverse and abundant when compared to healthy controls, but similar to sarcoidosis patients. This distal airway dysbiosis was attributed to the reduced presence of several genus (i.e., Actynomyces and Burkhordelia) as well as reported periodontopathic taxa, including Treponema, Prevotella, and Porphyromonas. While multiple clades correlated with local and systemic levels of autoantibodies, the genus Pseudonocardia and various related OTUs were the only taxa overrepresented in RA BAL and correlated with higher disease activity and erosions.ConclusionsDistal airway dysbiosis is present in untreated early RA and similar to that detected in sarcoidosis lung inflammation. This community perturbation, which correlates with local and systemic autoimmune/inflammatory changes, may potentially drive initiation of RA in a proportion of cases.

Tenascin-C and alpha-smooth muscle actin positive cells are increased in the large airways in patients with COPD

BackgroundChronic obstructive pulmonary disease (COPD) is characterized by inflammation and remodeling of the lungs. This results in alterations in extracellular matrix (ECM) and structural changes leading to airflow obstruction. We studied the expression of tenascin-C (Tn-C) and alpha smooth muscle actin (α-SMA), which act as a marker of myofibroblasts, in large airways from COPD patients. Our aim was to elucidate whether this expression correlated with smoking or with disease development.MethodsBronchoscopy was performed on 20 COPD patients (mean age 56 years; range 39-61; FEV1/FVC < 70% and FEV1 median 53% (range 33-69) of predicted). Age and smoking matched smokers (S) without COPD (n = 13) and age matched non-smokers (NS) (n = 14) served as controls. Bronchial mucosal biopsies were analyzed by immunohistochemistry. The distribution of Tn-C expression was assessed and graded in three levels, and the number of spindle shaped cells staining positive for α-SMA were counted.ResultsBiopsies from COPD patients had more (P < 0.001) Tn-C expression than the two control groups. A significantly (P < 0.05) increased number of spindle shaped cells expressing α-SMA was observed in COPD patients compared with the controls. Smokers and nonsmokers did not differ in this respect. The expression of Tn-C correlated positively (P < 0.001) to the number of α-SMA positive cells.ConclusionsWe demonstrate increased expression of Tn-C and α-SMA positive cells in the large airways in COPD. This was not associated to smoking per se, but to the presence of airway obstruction. Our findings add new information regarding remodeling characteristics and highlight the large airways as a potential site for airways obstruction in COPD.

Interleukin-26 in Antibacterial Host Defense of Human Lungs. Effects on Neutrophil Mobilization

RATIONALE The role of the presumed Th17 cytokine IL-26 in antibacterial host defense of the lungs is not known. OBJECTIVES To characterize the role of IL-26 in antibacterial host defense of human lungs. METHODS Intrabronchial exposure of healthy volunteers to endotoxin and vehicle was performed during bronchoscopy and bronchoalveolar lavage (BAL) samples were harvested. Intracellular IL-26 was detected using immunocytochemistry and immunocytofluorescence. This IL-26 was also detected using flow cytometry, as was its receptor complex. Cytokines and phosphorylated signal transducer and activator of transcription (STAT) 1 plus STAT3 were quantified using ELISA. Gene expression was analyzed by real-time polymerase chain reaction and neutrophil migration was assessed in vitro. MEASUREMENTS AND MAIN RESULTS Extracellular IL-26 was detected in BAL samples without prior exposure in vivo and was markedly increased after endotoxin exposure. Alveolar macrophages displayed gene expression for, contained, and released IL-26. Th and cytotoxic T cells also contained IL-26. In the BAL samples, IL-26 concentrations and innate effector cells displayed a correlation. Recombinant IL-26 potentiated neutrophil chemotaxis induced by IL-8 and fMLP but decreased chemokinesis for neutrophils. Myeloperoxidase in conditioned media from neutrophils was decreased. The IL-26 receptor complex was detected in neutrophils and IL-26 decreased phosphorylated STAT3 in these cells. In BAL and bronchial epithelial cells, IL-26 increased gene expression of the IL-26 receptor complex and STAT1 plus STAT3. Finally, IL-26 increased the release of neutrophil-mobilizing cytokines in BAL but not in epithelial cells. CONCLUSIONS This study implies that alveolar macrophages produce IL-26, which stimulates receptors on neutrophils and focuses their mobilization toward bacteria and accumulated immune cells in human lungs.

Differential inhibition of inflammatory cytokine release from cultured alveolar macrophages from smokers and non smokers by No2

Human alveolar macrophages (AMs) obtained from smokers and non-smokers by bronchoalveolar lavage (BAL) were subjected to various concentrations of NO2 in an inverted monolayer exposure model. Culture super natants were collected 4 h after the exposure and assayed for secreted TNF-α, IL-1β, IL-8 and MIP-1α. The steady state levels of the mRNAs for these cytokines were also analysed in the cells. The adherence of BAL cells to plastic prior to exposure to the gas elevated the steady state mRNA levels of all four cytokines tested in smokers cells and that of TNF-α and IL-1β, but not IL-8 (MIP-1α not tested), in non-smokers cells. Interestingly, adherent cells from non-smokers released circa 15-, 3-,1.5- and 3-fold the amounts of IL-1β, IL-8, TNF-α and MIP-1α, respectively, than smokers cells during control incubation or exposure to air. A 20 min exposure to NO2 (5 or 20 p.p.m.) did not increase the secretion of any of the cytokines from either cell type. In contrast, NO2 caused a concentration- dependent inhibition of the secretion of all cytokines except IL-1β from smokers cells. Additionally, NO2 greatly diminished the release of all cytokines in response to further treatment with lipopolysaccharide (LPS). In contrast, only the secretion of TNF-α from non-smokers cells was inhibited by the gas in a concentration- dependent manner, whilst LPS-induced secretion of the cytokines was not affected by the gas. The steady state levels of the respective mRNAs for each of the cytokines were not significantly affected in smokers cells by exposure to NO2, except for a negative, dose-dependent trend in the case of TNF-α. Nitrogen dioxide also failed to elevate the levels of the mRNAs in non-smokers cells but, again, tended to diminish the levels, particularly of IL-1β mRNA. However, exposure to the gas inhibited LPS- induced accumulation of cytokine mRNAs in smokers cells only. The data suggest that macrophage-derived cytokine mediators of the sepsis response may not play a role in the generation of NO2-induced inflammation in the human lung. Conversely, the gas seems to non-specifically inhibit the release and/or production of cytokines, particularly from smokers cells, at the post-transcrip tional level, and impairs the ability of the cells to increase the transcription and release of the cytokines in response to bacterial LPS. The fact that NO2 seriously impaired the already diminished capacity of smokers cells to release several important pro-inflammatory cytokines, both under control conditions and in response to LPS, strongly suggest that the inhalation of NO2 in cigarette smoke may contribute to impairing host defence against infection in the lung.

Bronchoalveolar lavage findings in firefighters

Firefighters are exposed to irritating, asphyxiating toxic gases and aerosols. Previous studies indicate that this may result in acute as well as chronic lung function impairment. It is well known that inhalation of organic material can cause alveolitis. The purpose of this study was to investigate whether firefighters repeatedly exposed to fire gases and other combustion products develop inflammatory changes in the lower airways and, if so, what subtype of cells and soluble components accumulate. Thirteen nonsmoking firefighters underwent bronchoalveolar lavage (BAL), and the results were compared to a reference group of 112 nonsmoking healthy volunteers. The firefighters showed lower recovery of instilled lavage fluid (61% vs 72%; P < 0.01) and an increase in the proportion of lymphocytes in that fluid (8.2% vs 5.7%; P < 0.05). Alveolar macrophage fluorescence, which is a sign of uptake of inhaled fluorescent material, rather than a reflection of the degree of inflammation, was increased in two firefighters. Further, the lavage fluid had higher concentrations of native fibronectin (34.6 vs 22.0 micrograms/L; P < 0.01) and hyaluronic acid (27.7 vs 10.0 micrograms/L; P < 0.05). This may indicate local cell activation, since the alveolar capillary membrane probably was intact, as indicated by an unaffected albumin concentration. The observed changes in the deep airways are probably caused by exposure to smoke. It cannot be concluded whether these changes are permanent or are part of a natural temporary defense mechanism.

Idiopathic pulmonary fibrosis in Sweden: report from the first year of activity of the Swedish IPF-Registry

Background Idiopathic pulmonary fibrosis (IPF) is an emerging problem in the western world, being related to increasing age and implying significant costs for the diagnosis and management of affected patients. The epidemiology of IPF is not well understood. Methods To allow estimates of the problem and eventually to evaluate quality of the care of IPF patients in Sweden, a national IPF Registry was started in the autumn of 2014. Data on criteria used to diagnose IPF, demographics, lung function, and quality of life (measured with the Kings Brief Interstitial Lung Disease Questionnaire, K-BILD) were reported directly to the registry, based at the coordinating centre (Karolinska University Hospital, Stockholm, Sweden) via a web-based platform. Results During the first year, the registry was implemented in 11 (33%) of the 33 respiratory units in the country. Seventy-one patients were registered between October 2014 and October 2015, 50 (70.4%) males and 21 (29.6%) females. Median age was 70 (range 47–86). The mean K-BILD score at the first inclusion in the registry was 54.3+9.5. Conclusions The main features of IPF patients in this first Swedish cohort were consistent with data published in the literature in main multinational randomized controlled trials. The K-BILD questionnaire showed that quality of life of patients with IPF and their perception of the disease are quite poor at the time of inclusion in the registry.

Identification of shared citrullinated immunological targets in the lungs and joints of patients with rheumatoid arthritis

Background The authors have previously demonstrated that smoking induces citrullination in the lungs of healthy smokers and they know that anticitrullinated protein antibodies (ACPA) develop in rheumatoid arthritis (RA) patients many years before disease onset. It was hypothesised that shared citrullinated targets are present in the lungs and joints of RA affected individuals and sought to investigate this by full-proteome analysis of synovial and lung biopsies of RA patients. Material and methods Proteins were extracted from synovial (n=7, five females and two males, median age 58, 66.7% ACPA positive) and lung (n=6, four females and two males, median age 63, 66.7% ACPA positive) biopsies of RA patients. Synovial biopsies were obtained at the time of open surgery from patients with long-standing RA (mean disease duration 24 years). Large bronchi biopsies were obtained by bronchoscopy from patients with newly diagnosed RA (three smokers and three non-smokers) with symptom duration less than 1 year. The proteins were reduced, alkylated and digested with Lys-C, separated by reverse-phase nanoflow-chromatography and analysed by LTQ-Velos-Orbitrap using multiple fragmentation methods. The data were searched against the human International Protein Index database using the Mascot search engine and all citrullinated peptides were manually verified. The degree of modification was quantified manually. The final results were expressed as ratios of citrullinated versus non-modified peptides. Results Over 3300 peptides and 500 proteins were identified in the different samples. The overall protein profiles varied between patients. Five of the identified proteins in the synovium (in total eight sites) and four in the lungs (in total four sites) contained citrullinated residues. Two vimentin derived citrullinated peptides were present in a majority of synovial and lung biopsies with slightly higher citrullinated/unmodified peptides ratios in smokers compared to non-smokers (median ratio of 0.03 in smokers and 0.02 in non-smokers for one of the peptides and a median ratio of 4.5 in the smokers and 0.04 in the non-smokers for the second vimentin peptide). While non-modified and citrullinated fibrinogen α-chain derived peptides were present in various amounts in the synovium, only the unmodified sites could be detected in the lungs of a subset of the patients (three out of six). Conclusions The authors demonstrate the presence of shared in vivo citrullinated proteins in the joints and lungs of RA individuals, providing further support for the important pathogenic link between joints and lungs in development of RA.

Organisation of diagnosis and treatment of idiopathic pulmonary fibrosis and other interstitial lung diseases in the Nordic countries

Introduction Differences in the organisation of idiopathic pulmonary fibrosis (IPF) and interstitial lung diseases (ILDs) in the Nordic countries are not well described. Diagnostic setups, treatment modalities and follow-up plans may vary due to national, cultural and epidemiological features. The aim of the present study was to describe the different organisation of diagnostics and treatment of IPF and ILD in the Nordic countries. Methods All university and regional hospitals with respiratory physicians were invited to respond to a questionnaire collecting data on the number of physicians, nurses, patients with ILD/IPF, the presence of and adherence to disease-specific national and international guidelines, diagnosis and treatment including ILD-specific palliation and rehabilitation programmes. Results Twenty-four university and 22 regional hospitals returned the questionnaire. ILD and IPF incidence varied between 1.4 and 20/100,000 and 0.4 and 10/100,000, respectively. Denmark and Estonia have official national plans for the organisation of ILD. The majority of patients are managed at the university hospitals. The regional hospitals each manage 46 (5–200) patients with ILD and 10 (0–20) patients with IPF. There are from one to four ILD centres in each country with a median of two ILD specialists employed. Specialised ILD nurses are present in nine hospitals. None of the Nordic countries have national guidelines made by health authorities. The respiratory societies in Sweden, Norway and Denmark have developed national guidelines. All hospitals except two use the ATS/ERS/JRS/ALAT IPF guidelines from 2011. The limited number of ILD specialists, ILD-specialised radiologists and pathologists and the low volume of ILD centres were perceived as bottlenecks for implementation of guidelines. Twenty of the 24 university hospitals have multidisciplinary conferences (MDCs). Pulmonologists and radiologists take part in all MDCs while pathologists only participate at 17 hospitals. Prescription of pirfenidone is performed by all university hospitals except in Estonia. Triple therapy with steroid, azathioprine and N-acetylcysteine is not used. No hospitals have specific palliation programmes for patients with ILD/IPF, but 36 hospitals have the possibility of referring patients for palliative care, mostly based on existing oncology palliative care teams; seven hospitals have rehabilitation programmes for ILD. Conclusion There are obvious differences between the organisations of ILD patients in the Nordic countries. We call for national plans that consider the challenge of cultural and geographical differences and suggest the establishment of national reference centres and satellite collaborative hospitals to enable dev