Single Cell Analysis Reveals Novel Immune Perturbations in Fibrotic Hypersensitivity Pneumonitis.

Rationale: Fibrotic hypersensitivity pneumonitis is a debilitating interstitial lung disease driven by incompletely understood immune mechanisms. Objectives: To elucidate immune aberrations in fibrotic hypersensitivity pneumonitis in single-cell resolution. Methods: Single-cell 5' RNA sequencing was conducted on peripheral blood mononuclear cells and bronchoalveolar lavage cells obtained from 45 patients with fibrotic hypersensitivity pneumonitis, 63 idiopathic pulmonary fibrosis, 4 non-fibrotic hypersensitivity pneumonitis, and 36 healthy controls in the United States and Mexico. Analyses included differential gene expression (Seurat), transcription factor activity imputation (DoRothEA-VIPER), and trajectory analyses (Monocle3/Velocyto-scVelo-CellRank). Measurements and Main Results: Overall, 501,534 peripheral blood mononuclear cells from 110 patients and controls and 88,336 bronchoalveolar lavage cells from 19 patients were profiled. Compared to controls, fibrotic hypersensitivity pneumonitis has elevated classical monocytes (adjusted-p=2.5e-3) and are enriched in CCL3hi/CCL4hi and S100Ahi classical monocytes (adjusted-p<2.2e-16). Trajectory analyses demonstrate that S100Ahi classical monocytes differentiate into SPP1hi lung macrophages associated with fibrosis. Compared to both controls and idiopathic pulmonary fibrosis, fibrotic hypersensitivity pneumonitis patient cells are significantly enriched in GZMhi cytotoxic T cells. These cells exhibit transcription factor activities indicative of TGFß and TNFα/NFκB pathways. These results are publicly available at https://ildimmunecellatlas.org. Conclusions: Single-cell transcriptomics of fibrotic hypersensitivity pneumonitis patients uncovered novel immune perturbations, including previously undescribed increases in GZMhi cytotoxic CD4+ and CD8+ T cells - reflecting this disease's unique inflammatory T-cell driven nature - as well as increased S100Ahi and CCL3hi/CCL4hi classical monocytes also observed in idiopathic pulmonary fibrosis. Both cell populations may guide the development of new biomarkers and therapeutic interventions.

Increased expression of CXCL6 in secretory cells drives fibroblast collagen synthesis and is associated with increased mortality in idiopathic pulmonary fibrosis.

RATIONALE: Recent data suggest that the localisation of airway epithelial cells in the distal lung in idiopathic pulmonary fibrosis (IPF) may drive pathology. We set out to discover whether chemokines expressed in these ectopic airway epithelial cells may contribute to the pathogenesis of IPF. METHODS: We analysed whole lung and single-cell transcriptomic data obtained from patients with IPF. In addition, we measured chemokine levels in blood, bronchoalveolar lavage (BAL) of IPF patients and air-liquid interface cultures. We employed ex vivo donor and IPF lung fibroblasts and an animal model of pulmonary fibrosis to test the effects of chemokine signalling on fibroblast function. RESULTS: By analysis of whole-lung transcriptomics, protein and BAL, we discovered that CXCL6 (a member of the interleukin-8 family) was increased in patients with IPF. Elevated CXCL6 levels in the BAL of two cohorts of patients with IPF were associated with poor survival (hazard ratio of death or progression 1.89, 95% CI 1.16-3.08; n=179, p=0.01). By immunostaining and single-cell RNA sequencing, CXCL6 was detected in secretory cells. Administration of mCXCL5 (LIX, murine CXCL6 homologue) to mice increased collagen synthesis with and without bleomycin. CXCL6 increased collagen I levels in donor and IPF fibroblasts 4.4-fold and 1.7-fold, respectively. Both silencing of and chemical inhibition of CXCR1/2 blocked the effects of CXCL6 on collagen, while overexpression of CXCR2 increased collagen I levels 4.5-fold in IPF fibroblasts. CONCLUSIONS: CXCL6 is expressed in ectopic airway epithelial cells. Elevated levels of CXCL6 are associated with IPF mortality. CXCL6-driven collagen synthesis represents a functional consequence of ectopic localisation of airway epithelial cells in IPF.

The use of cultured human alveolar basal cells to mimic honeycomb formation in idiopathic pulmonary fibrosis.

BACKGROUND: Honeycomb cysts (HC) within the alveolar region are distinct histopathological features in the lungs of idiopathic pulmonary fibrosis (IPF) patients. HC are lined with a single-or stratified layer of basal cells (BC), or with a bronchiolar-like epithelium composed of basal-, ciliated- and secretory epithelial cells. By using cultured IPF patient-derived alveolar BC, we aimed to establish an in vitro- and in vivo model to mimic HC formation in IPF. We (1) optimized conditions to culture and propagate IPF patient-derived alveolar BC, (2) cultured the cells on an air liquid interface (ALI) or in a three dimensional (3D) organoid model, and (3) investigated the cells` behavior after instillation into bleomycin-challenged mice. METHODS: Alveolar BC were cultured from peripheral IPF lung tissue and grown on tissue-culture treated plastic, an ALI, or in a 3D organoid model. Furthermore, cells were instilled into bleomycin-challenged NRG mice. Samples were analyzed by TaqMan RT-PCR, immunoblotting, immunocytochemistry/immunofluorescence (ICC/IF), or immunohistochemistry (IHC)/IF. Mann-Whitney tests were performed using GraphPad Prism software. RESULTS: Cultured alveolar BC showed high expression of canonical basal cell markers (TP63, keratin (KRT)5, KRT14, KRT17), robust proliferation, and wound closure capacity. The cells could be cryopreserved and propagated for up to four passages without a significant loss of basal cell markers. When cultured on an ALI or in a 3D organoid model, alveolar BC differentiated to ciliated- and secretory epithelial cells. When instilled into bleomycin-challenged mice, human alveolar BC cells formed HC-like structures composed of human basal-, and secretory epithelial cells within the mouse parenchyma. CONCLUSION: IPF patient-derived alveolar BC on an ALI, in 3D organoids or after instillation into bleomycin-challenged mice form HC-like structures that closely resemble HC within the IPF lung. These models therefore represent powerful tools to study honeycomb formation, and its potential therapeutic inhibition in IPF.

Blood T cell phenotypes correlate with fatigue severity in post-acute sequelae of COVID-19.

PURPOSE: Post-acute sequelae of COVID-19 (PASC) affect approximately 10% of convalescent patients. The spectrum of symptoms is broad and heterogeneous with fatigue being the most often reported sequela. Easily accessible blood biomarkers to determine PASC severity are lacking. Thus, our study aimed to correlate immune phenotypes with PASC across the severity spectrum of COVID-19. METHODS: A total of 176 originally immunonaïve, convalescent COVID-19 patients from a prospective cohort during the first pandemic phase were stratified by initial disease severity and underwent clinical, psychosocial, and immune phenotyping around 10 weeks after first COVID-19 symptoms. COVID-19-associated fatigue dynamics were assessed and related to clinical and immune phenotypes. RESULTS: Fatigue and severe fatigue were commonly reported irrespective of initial COVID-19 severity or organ-specific PASC. A clinically relevant increase in fatigue severity after COVID-19 was detected in all groups. Neutralizing antibody titers were higher in patients with severe acute disease, but no association was found between antibody titers and PASC. While absolute peripheral blood immune cell counts in originally immunonaïve PASC patients did not differ from unexposed controls, peripheral CD3+CD4+ T cell counts were independently correlated with fatigue severity across all strata in multivariable analysis. CONCLUSIONS: Patients were at similar risk of self-reported PASC irrespective of initial disease severity. The independent correlation between fatigue severity and blood T cell phenotypes indicates a possible role of CD4+ T cells in the pathogenesis of post-COVID-19 fatigue, which might serve as a blood biomarker.

The efficacy and safety of systemic corticosteroids as first line treatment for granulomatous lymphocytic interstitial lung disease.

BACKGROUND: Granulomatous and lymphocytic interstitial lung disease (gl-ILD) is a major cause of morbidity and mortality among patients with common variable immunodeficiency. Corticosteroids are recommended as first-line treatment for gl-ILD, but evidence for their efficacy is lacking. OBJECTIVES: This study analyzed the effect of high-dose corticosteroids (≥0.3 mg/kg prednisone equivalent) on gl-ILD, measured by high-resolution computed tomography (HRCT) scans, and pulmonary function test (PFT) results. METHODS: Patients who had received high-dose corticosteroids but no other immunosuppressive therapy at the time (n = 56) and who underwent repeated HRCT scanning or PFT (n = 39) during the retrospective and/or prospective phase of the Study of Interstitial Lung Disease in Primary Antibody Deficiency (STILPAD) were included in the analysis. Patients without any immunosuppressive treatment were selected as controls (n = 23). HRCT scans were blinded, randomized, and scored using the Hartman score. Differences between the baseline and follow-up HRCT scans and PFT were analyzed. RESULTS: Treatment with high-dose corticosteroids significantly improved HRCT scores and forced vital capacity. Carbon monoxide diffusion capacity significantly improved in both groups. Of 18 patients, for whom extended follow-up data was available, 13 achieved a long-term, maintenance therapy independent remission. All patients with relapse were retreated with corticosteroids, but only one-fifth of them responded. Two opportunistic infections were found in the corticosteroid treatment group, while overall infection rate was similar between cohorts. CONCLUSIONS: Induction therapy with high-dose corticosteroids improved HRCT scans and PFT results of patients with gl-ILD and achieved long-term remission in 42% of patients. It was not associated with major side effects. Low-dose maintenance therapy provided no benefit and efficacy was poor in relapsing disease.

[Therapeutic Pathways in Sarcoidosis. A Position Paper of the German Society of Respiratory Medicine (DGP)]. / Therapie der Sarkoidose. Ein Positionspapier der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin (DGP).

The present recommendations on the therapy of sarcoidosis of the German Respiratory Society (DGP) was written in 2023 as a German-language supplement and update of the international guidelines of the European Respiratory Society (ERS) from 2021. It contains 5 PICO questions (Patients, Intervention, Comparison, Outcomes) agreed in the consensus process, which are explained in the background text of the four articles: Confirmation of diagnosis and monitoring of the disease under therapy, general therapy recommendations, therapy of cutaneous sarcoidosis, therapy of cardiac sarcoidosis.

European Respiratory Society statement on familial pulmonary fibrosis.

Genetic predisposition to pulmonary fibrosis has been confirmed by the discovery of several gene mutations that cause pulmonary fibrosis. Although genetic sequencing of familial pulmonary fibrosis (FPF) cases is embedded in routine clinical practice in several countries, many centres have yet to incorporate genetic sequencing within interstitial lung disease (ILD) services and proper international consensus has not yet been established. An international and multidisciplinary expert Task Force (pulmonologists, geneticists, paediatrician, pathologist, genetic counsellor, patient representative and librarian) reviewed the literature between 1945 and 2022, and reached consensus for all of the following questions: 1) Which patients may benefit from genetic sequencing and clinical counselling? 2) What is known of the natural history of FPF? 3) Which genes are usually tested? 4) What is the evidence for telomere length measurement? 5) What is the role of common genetic variants (polymorphisms) in the diagnostic workup? 6) What are the optimal treatment options for FPF? 7) Which family members are eligible for genetic sequencing? 8) Which clinical screening and follow-up parameters may be considered in family members? Through a robust review of the literature, the Task Force offers a statement on genetic sequencing, clinical management and screening of patients with FPF and their relatives. This proposal may serve as a basis for a prospective evaluation and future international recommendations.

MUC5B rs35705950 minor allele associates with older age and better survival in idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: The minor T-allele of the MUC5B promoter polymorphism rs35705950 is strongly associated with idiopathic pulmonary fibrosis (IPF). However, conflicting results have been reported on the relationship between the MUC5B minor allele and survival and it is unknown whether a specific subgroup of IPF patients might benefit from MUC5B minor allele carriage. We investigated the association between MUC5B rs35705950, survival and patient characteristics in a real-world population of European IPF patients. METHODS: In this retrospective study, 1751 patients with IPF from 8 European centres were included. MUC5B rs35705950 genotype, demographics, clinical characteristics at diagnosis and survival data were analysed. RESULTS: In a multi-variate Cox proportional hazard model the MUC5B minor allele was a significant independent predictor of survival when adjusted for age, sex, high resolution computed tomography pattern, smoking behaviour and pulmonary function tests in IPF. MUC5B minor allele carriers were significantly older at diagnosis (p = 0.001). The percentage of MUC5B minor allele carriers increased significantly with age from 44% in patients aged <56 year, to 63% in patients aged >75. In IPF patients aged <56, the MUC5B minor allele was not associated with survival. In IPF patients aged ≥56, survival was significantly better for MUC5B minor allele carriers (45 months [CI: 42-49]) compared to non-carriers (29 months [CI: 26-33]; p = 4 × 10-12 ). CONCLUSION: MUC5B minor allele carriage associates with a better median transplant-free survival of 16 months in the European IPF population aged over 56 years. MUC5B genotype status might aid disease prognostication in clinical management of IPF patients.

A Phase IIb Randomized Clinical Study of an Anti-αvß6 Monoclonal Antibody in Idiopathic Pulmonary Fibrosis.

Rationale: Treatment options for idiopathic pulmonary fibrosis (IPF) are limited. Objectives: To evaluate the efficacy and safety of BG00011, an anti-αvß6 IgG1 monoclonal antibody, in the treatment of patients with IPF. Methods: In a phase IIb randomized, double-blind, placebo-controlled trial, patients with IPF (FVC ⩾50% predicted, on or off background therapy) were randomized 1:1 to once-weekly subcutaneous BG00011 56 mg or placebo. The primary endpoint was FVC change from baseline at Week 52. Because of early trial termination (imbalance in adverse events and lack of clinical benefit), endpoints were evaluated at Week 26 as an exploratory analysis. Measurements and Main Results: One hundred six patients were randomized and received at least one dose of BG00011 (n = 54) or placebo (n = 52). At Week 26, there was no significant difference in FVC change from baseline between patients who received BG00011 (n = 20) or placebo (n = 23), least squares mean (SE) -0.097 L (0.0600) versus -0.056 L (0.0593), respectively (P = 0.268). However, after Week 26, patients in the BG00011 group showed a worsening trend. Eight (44.4%) of 18 who received BG00011 and 4 (18.2%) of 22 who received placebo showed worsening of fibrosis on high-resolution computed tomography at the end of treatment. IPF exacerbation/or progression was reported in 13 patients (all in the BG00011 group). Serious adverse events occurred more frequently in BG00011 patients, including four deaths. Conclusions: The results do not support the continued clinical development of BG00011. Further research is warranted to identify new treatment strategies that modify inflammatory and fibrotic pathways in IPF. Clinical trial registered with www.clinicaltrials.gov (NCT03573505).

Investigating significant health trends in progressive fibrosing interstitial lung disease (INSIGHTS-ILD): rationale, aims and design of a nationwide prospective registry.

BACKGROUND: The progressive course of pulmonary fibrosis (PPF) is observed with variable prevalence in different entities of fibrosing interstitial lung disease (fILD). PPF is characterised by worsening respiratory symptoms, declining lung function and increasing extent of fibrosis on high-resolution computer tomography. In Germany, data are limited on the characteristics and management of such patients. METHODS/DESIGN: INSIGHTS-ILD is a prospective observational longitudinal registry designed to describe characteristics, management and course of newly diagnosed (incident) and prevalent patients with fILD on the long term. The registry uses a non-probability sampling approach to collect data on characteristics, therapeutic interventions, health-related quality of life and health economic parameters. It is planned to include 900 patients in ambulatory care in about 30 expert sites over three years. The study has been initiated in December 2021, and currently (January 2023) follows 360 patients. DISCUSSION: The registry is expected to provide much-needed data on the characteristics, management, and trajectories of patients fILD in Germany. The start of the study comes at a time when new treatment options are available for PPF. We hypothesize that PPF represents a broad clinical phenotype that is differentially influenced by inflammatory and fibrotic pathomechanisms that need to be treated with anti-inflammatory and/or anti-fibrotic treatment strategies. This registry will allow comparisons with other countries. Gap analyses based on current guidelines for management of these patients will be possible. Trial registration DRKS00027389 (registered on 7.12.2021), BfArM NIS 7562.

[Practicable diagnostics of Sjögren's syndrome in interstitial lung disease-A discussion article]. / Praktikable Sjögren-Diagnostik bei interstitieller Lungenerkrankung ­ ein Diskussionsbeitrag.

Sjögren's syndrome (SjS) is a possible autoimmune cause of interstitial lung disease. The diagnostic pathway for SjS, however, is largely undefined in comparison to other systemic autoimmune diseases. Subjective sicca symptoms, anti-SS-A/Ro antibodies and even ANA as screening tests all have relevant limitations in sensitivity and/or specificity. Against this background, in an interdisciplinary discussion we have developed a consensus for the clarification of SjS, which is presented here for broader discussion. In addition to ANA and anti-SS-A/Ro antibodies, antibodies against alpha-fodrin should be included. Objective measures of dryness, such a Schirmer and Saxon tests are important, as is a salivary gland biopsy in the absence of typical autoantibodies.

[SARS-CoV-2-Infection and Interstitial Lung Disease: Position paper of the German Respiratory Society]. / SARS-CoV-2-Infektion und interstitielle Lungenerkrankungen ­ Positionspapier der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin.

The SARS-CoV-2 pandemic had a tremendous impact on diagnosis and treatment of interstitial lung diseases (ILD). Especially in the early phase of the pandemic, when the delta variant was prevailling, a huge number of viral pneumonias were observed, which worsened pre-existing, triggered de novo occurence or discovery of previously subclincal interstitial lung diseases. The effect of SARS-CoV-2 infection - without or with accompanying viral pneumonia - on the further development of pre-existing ILD as well of new pulmonary inflitrates and consolidiations is difficult to predict and poses a daily challenge to interdisciplinary ILD boards. This position paper of the German Respiratory Society (DGP e.V.) provides answers to the most pressing questions based on current knowledge.

[Consensus guideline on the interdisciplinary diagnosis of interstitial lung diseases]. / S1-Leitlinie Interdisziplinäre Diagnostik interstitieller Lungenerkrankungen im Erwachsenenalter.

The evaluation of a patient with interstitial lung disease (ILD) includes assessment of clinical, radiological, and often histopathological data. As there were no specific recommendations to guide the evaluation of patients under the suspicion of an ILD within the German practice landscape, this position statement from an interdisciplinary panel of ILD experts provides guidance related to the diagnostic modalities which should be used in the evaluation of ILD. This includes clinical assessment rheumatological evaluation, radiological examinations, histopathologic sampling and the need for a final discussion in a multidisciplinary team.

Increased regional ventilation as early imaging marker for future disease progression of interstitial lung disease: a feasibility study.

OBJECTIVES: Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly variable course. Pathologically increased ventilation-accessible by functional CT-is discussed as a potential predecessor of lung fibrosis. The purpose of this feasibility study was to investigate whether increased regional ventilation at baseline CT and morphological changes in the follow-up CT suggestive for fibrosis indeed occur in spatial correspondence. METHODS: In this retrospective study, CT scans were performed at two time points between September 2016 and November 2020. Baseline ventilation was divided into four categories ranging from low, normal to moderately, and severely increased (C1-C4). Correlation between baseline ventilation and volume and density change at follow-up was investigated in corresponding voxels. The significance of the difference of density and volume change per ventilation category was assessed using paired t-tests with a significance level of p ≤ 0.05. The analysis was performed separately for normal (NAA) and high attenuation areas (HAA). RESULTS: The study group consisted of 41 patients (73 ± 10 years, 36 men). In both NAA and HAA, significant increases of density and loss of volume were seen in areas of severely increased ventilation (C4) at baseline compared to areas of normal ventilation (C2, p < 0.001). In HAA, morphological changes were more heterogeneous compared to NAA. CONCLUSION: Functional CT assessing the extent and distribution of lung parenchyma with pathologically increased ventilation may serve as an imaging marker to prospectively identify lung parenchyma at risk for developing fibrosis. KEY POINTS: • Voxelwise correlation of serial CT scans suggests spatial correspondence between increased ventilation at baseline and structural changes at follow-up. • Regional assessment of pathologically increased ventilation at baseline has the potential to prospectively identify tissue at risk for developing fibrosis. • Presence and extent of pathologically increased ventilation may serve as an early imaging marker of disease activity.

Genetic testing in interstitial lung disease: An international survey.

BACKGROUND AND OBJECTIVE: Genetic analysis is emerging for interstitial lung diseases (ILDs); however, ILD practices are not yet standardized. We surveyed patients', relatives' and pulmonologists' experiences and needs on genetic testing in ILD to evaluate the current situation and identify future needs. METHODS: A clinical epidemiologist (MT) together with members of the ERS taskforce and representatives of the European Idiopathic Pulmonary Fibrosis and related disorders Federation (EU-IPFF) patient organisation developed a survey for patients, relatives and pulmonologists. Online surveys consisted of questions on five main topics: awareness of hereditary ILD, the provision of information, genetic testing, screening of asymptomatic relatives and clinical impact of genetic analysis in ILD. RESULTS: Survey respondents consisted of 458 patients with ILD, 181 patients' relatives and 352 pulmonologists. Most respondents think genetic testing can be useful, particularly for explaining the cause of disease, predicting its course, determining risk for developing disease and the need to test relatives. Informing patients and relatives on genetic analysis is primarily performed by the pulmonologist, but 88% (218) of pulmonologists identify a need for more information and 96% (240) ask for guidelines on genetic testing in ILD. A third of the pulmonologists who would offer genetic testing currently do not offer a genetic test, primarily because they have limited access to genetic tests. Following genetic testing, 72% (171) of pulmonologists may change the diagnostic work-up and 57% (137) may change the therapeutic approach. CONCLUSION: This survey shows that there is wide support for implementation of genetic testing in ILD and a high need for information, guidelines and access to testing among patients, their relatives and pulmonologists.

Surgical Lung Biopsy for Interstitial Lung Disease: A Two Center Propensity Score Matching Analysis.

BACKGROUND: Surgical lung biopsy (SLB) is recommended for patients with nonclassified interstitial lung disease (nILD) if high resolution computed tomography and/or transbronchial lung biopsy did not achieve a definitive diagnosis. Current literature suggests better patient tolerability and less postoperative complications if surgery is performed under spontaneous ventilation. OBJECTIVES: We conducted a propensity score matching (PSM) analysis of our nILD patients undergoing SLB under spontaneous ventilation or general anesthesia to investigate postprocedural AE-ILD, 30-/90-day mortality and perioperative variables in two academic high-volume centers (Hannover, Heidelberg). METHODS: All patients undergoing SLB for nILD under general anesthesia (GAVATS) and spontaneous ventilation (NIVATS) at both centers from February 2013 until April 2021 were analyzed retrospectively. Data of 132 patients were used for PSM resulting in 40 pairs. RESULTS: There was one death in the NIVATS group 60 days after SLB and one AE-ILD in each cohort. Chest tube indwelling time, chest tube total effusion, length of hospital stay, and operative time were all in favor of NIVATS. CONCLUSIONS: In our PSM analysis, NIVATS is associated with faster postprocedural recovery. However, a reduction in postoperative AE-ILD or 30-/90-day mortality was not observed.

A New Tool to Assess Quality of Life in Patients with Idiopathic Pulmonary Fibrosis or Non-specific Interstitial Pneumonia.

BACKGROUND: Quality of life (QoL) is significantly impaired in patients with pulmonary fibrosis, however reliable tools to assess QoL issues specific for this group of patients are still missing. We thus aimed to develop a new questionnaire called "Quality of life in patients with idiopathic pulmonary fibrosis" (QPF) to measure QoL in patients with fibrotic idiopathic interstitial pneumonias (IIP). METHODS: An item pool was created on the basis of a German expert group with support of patients suffering from pulmonary fibrosis. In a 1st step, this version of the questionnaire was completed by 52 patients with idiopathic pulmonary fibrosis (IPF) or non-specific interstitial pneumonia (NSIP). Following this, an item- and an exploratory factor analysis was carried out and a 2nd version created. In a multicenter validation study in a one-group pre-post design, the questionnaire was filled in by 200 patients with IIP (IPF = 190, iNSIP = 10) at 2 time points with an interval of 6 months. Cross-validation was carried out with the St. Georges Respiratory Questionnaire (SGRQ). RESULTS: The mean age of the patients was 71.0 years (50-90 years), 82.5 % were male. Item analysis revealed that most of Cronbach alpha and selectivity values of QPF-scales could be considered as sufficient (e. g. QPF-scale "condition" [alpha = 0.827], "impairment" [alpha = 0.882]). At scale level, there were significant differences in terms of a deterioration or improvement in the QPF-condition and QPF-breathlessness scales and also in the SGRQ-activity scale. Analysis of construct validation of QPF and SGRQ showed moderate correlations between both questionnaires. A deterioration in health status from the patient's and doctor's perspective was seen in the scales "impairment", "shortness of breath" and "health status" of the QPF. The QPF was able to detect a change in the patient's mood ("condition" scale) in the course of treatment. CONCLUSION: This newly developed questionnaire maps the special needs of the patients well. The QPF is suitable for screening of quality of life as well as for supplementing the medical history and for monitoring the course of disease in fibrotic IIPs.

Transcriptomics of bronchoalveolar lavage cells identifies new molecular endotypes of sarcoidosis.

BACKGROUND: Sarcoidosis is a multisystem granulomatous disease of unknown origin with a variable and often unpredictable course and pattern of organ involvement. In this study we sought to identify specific bronchoalveolar lavage (BAL) cell gene expression patterns indicative of distinct disease phenotypic traits. METHODS: RNA sequencing by Ion Torrent Proton was performed on BAL cells obtained from 215 well-characterised patients with pulmonary sarcoidosis enrolled in the multicentre Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS) study. Weighted gene co-expression network analysis and nonparametric statistics were used to analyse genome-wide BAL transcriptome. Validation of results was performed using a microarray expression dataset of an independent sarcoidosis cohort (Freiburg, Germany; n=50). RESULTS: Our supervised analysis found associations between distinct transcriptional programmes and major pulmonary phenotypic manifestations of sarcoidosis including T-helper type 1 (Th1) and Th17 pathways associated with hilar lymphadenopathy, transforming growth factor-ß1 (TGFB1) and mechanistic target of rapamycin (MTOR) signalling with parenchymal involvement, and interleukin (IL)-7 and IL-2 with airway involvement. Our unsupervised analysis revealed gene modules that uncovered four potential sarcoidosis endotypes including hilar lymphadenopathy with increased acute T-cell immune response; extraocular organ involvement with PI3K activation pathways; chronic and multiorgan disease with increased immune response pathways; and multiorgan involvement, with increased IL-1 and IL-18 immune and inflammatory responses. We validated the occurrence of these endotypes using gene expression, pulmonary function tests and cell differentials from Freiburg. CONCLUSION: Taken together, our results identify BAL gene expression programmes that characterise major pulmonary sarcoidosis phenotypes and suggest the presence of distinct disease molecular endotypes.

Quantification of dual-energy CT-derived functional parameters as potential imaging markers for progression of idiopathic pulmonary fibrosis.

OBJECTIVES: The individual course of disease in idiopathic pulmonary fibrosis (IPF) is highly variable. Assessment of disease activity and prospective estimation of disease progression might have the potential to improve therapy management and indicate the onset of treatment at an earlier stage. The aim of this study was to evaluate whether regional ventilation, lung perfusion, and late enhancement can serve as early imaging markers for disease progression in patients with IPF. METHODS: In this retrospective study, contrast-enhanced dual-energy CT scans of 32 patients in inspiration and delayed expiration were performed at two time points with a mean interval of 15.4 months. The pulmonary blood volume (PBV) images obtained in the arterial and delayed perfusion phase served as a surrogate for arterial lung perfusion and parenchymal late enhancement. The virtual non-contrast (VNC) images in inspiration and expiration were non-linearly registered to provide regional ventilation images. Image-derived parameters were correlated with longitudinal changes of lung function (FVC%, DLCO%), mean lung density in CT, and CT-derived lung volume. RESULTS: Regional ventilation and late enhancement at baseline preceded future change in lung volume (R - 0.474, p 0.006/R - 0.422, p 0.016, respectively) and mean lung density (R - 0.469, p 0.007/R - 0.402, p 0.022, respectively). Regional ventilation also correlated with a future change in FVC% (R - 0.398, p 0.024). CONCLUSION: CT-derived functional parameters of regional ventilation and parenchymal late enhancement are potential early imaging markers for idiopathic pulmonary fibrosis progression. KEY POINTS: • Functional CT parameters at baseline (regional ventilation and late enhancement) correlate with future structural changes of the lung as measured with loss of lung volume and increase in lung density in serial CT scans of patients with idiopathic pulmonary fibrosis. • Functional CT parameter measurements in high-attenuation areas (- 600 to - 250 HU) are significantly different from normal-attenuation areas (- 950 to - 600 HU) of the lung. • Mean regional ventilation in functional CT correlates with a future change in forced vital capacity (FVC) in pulmonary function tests.

Role of endothelial microRNA 155 on capillary leakage in systemic inflammation.

BACKGROUND: Capillary leakage is a key contributor to the pathological host response to infections. The underlying mechanisms remain incompletely understood, and the role of microRNAs (MIR) has not been investigated in detail. We hypothesized that specific MIRs might be regulated directly in the endothelium thereby contributing to vascular leakage. METHODS: SmallRNA sequencing of endotoxemic murine pulmonary endothelial cells (ECs) was done to detect regulated vascular MIRs. In vivo models: transgenic zebrafish (flk1:mCherry/l-fabp:eGFP-DPB), knockout/wildtype mouse (B6.Cg-Mir155tm1.1Rsky/J); disease models: LPS 17.5 mg/kgBW and cecal ligation and puncture (CLP); in vitro models: stimulated human umbilical vein EC (HUVECs), transendothelial electrical resistance. RESULTS: Endothelial MIR155 was identified as a promising candidate in endotoxemic murine pulmonary ECs (25 × upregulation). Experimental overexpression in a transgenic zebrafish line and in HUVECs was sufficient to induce spontaneous vascular leakage. To the contrary, genetic MIR155 reduction protects against permeability both in vitro and in endotoxemia in vivo in MIR155 heterozygote knockout mice thereby improving survival by 40%. A tight junction protein, Claudin-1, was down-regulated both in endotoxemia and by experimental MIR155 overexpression. Translationally, MIR155 was detectable at high levels in bronchoalveolar fluid of patients with ARDS compared to healthy human subjects. CONCLUSIONS: We found that MIR155 is upregulated in the endothelium in mouse and men as part of a systemic inflammatory response and might contribute to the pathophysiology of vascular leakage in a Claudin-1-dependent manner. Future studies have to clarify whether MIR155 could be a potential therapeutic target.