Animal and human studies support the importance of the coagulation cascade in pulmonary fibrosis.
In a cohort of subjects with progressive idiopathic pulmonary fibrosis (IPF), we tested the ...hypothesis that treatment with warfarin at recognized therapeutic doses would reduce rates of mortality, hospitalization, and declines in FVC.
This was a double-blind, randomized, placebo-controlled trial of warfarin targeting an international normalized ratio of 2.0 to 3.0 in patients with IPF. Subjects were randomized in a 1:1 ratio to warfarin or matching placebo for a planned treatment period of 48 weeks. International normalized ratios were monitored using encrypted home point-of-care devices that allowed blinding of study therapy.
The primary outcome measure was the composite outcome of time to death, hospitalization (nonbleeding, nonelective), or a 10% or greater absolute decline in FVC. Due to a low probability of benefit and an increase in mortality observed in the subjects randomized to warfarin (14 warfarin versus 3 placebo deaths; P = 0.005) an independent Data and Safety Monitoring Board recommended stopping the study after 145 of the planned 256 subjects were enrolled (72 warfarin, 73 placebo). The mean follow-up was 28 weeks.
This study did not show a benefit for warfarin in the treatment of patients with progressive IPF. Treatment with warfarin was associated with an increased risk of mortality in an IPF population who lacked other indications for anticoagulation.
Little is known about health risks associated with electronic cigarette (EC) use although EC are rising in popularity and have been advocated as a means to quit smoking cigarettes.
Ten never-smokers, ...without exposure history to tobacco products or EC, were assessed at baseline with questionnaire, chest X-ray, lung function, plasma levels of endothelial microparticles (EMP), and bronchoscopy to obtain small airway epithelium (SAE) and alveolar macrophages (AM). One week later, subjects inhaled 10 puffs of "Blu" brand EC, waited 30 min, then another 10 puff; n = 7 were randomized to EC with nicotine and n = 3 to EC without nicotine to assess biological responses in healthy, naive individuals.
Two hr. post-EC exposure, subjects were again assessed as at baseline. No significant changes in clinical parameters were observed. Biological changes were observed compared to baseline, including altered transcriptomes of SAE and AM for all subjects and elevated plasma EMP levels following inhalation of EC with nicotine.
This study provides in vivo human data demonstrating that acute inhalation of EC aerosols dysregulates normal human lung homeostasis in a limited cohort of healthy naïve individuals. These observations have implications to new EC users, nonsmokers exposed to secondhand EC aerosols and cigarette smokers using EC to quit smoking.
ClinicalTrials.gov NCT01776398 (registered 10/12/12), NCT02188511 (registered 7/2/14).
Biomarkers have the potential to become central to the clinical evaluation and monitoring of patients with chronic fibrosing interstitial lung diseases (ILDs) with a progressive phenotype. Here we ...summarize the current understanding of putative serum, BAL fluid, and genetic biomarkers in this setting, according to their hypothesized pathobiologic mechanisms: evidence of epithelial cell dysfunction (eg, Krebs von den Lungen-6 antigen), fibroblast proliferation and extracellular matrix production or turnover (eg, matrix metalloproteinase-1), or immune dysregulation (eg, CC chemokine ligand 18). While most of the available data come from idiopathic pulmonary fibrosis (IPF), the prototypic progressive fibrosing ILD, data are available in the broader patient population of chronic fibrosing ILDs. A number of these biomarkers show promise, however, none have been validated. In this review article, we assess both the status of proposed biomarkers for chronic fibrosing lung diseases with a progressive phenotype in predicting disease risk or predisposition, diagnosis, prognosis, and treatment response and provide a direct comparison between IPF and other chronic fibrotic ILDs. We also reflect on the current clinical usefulness and future direction of research for biomarkers in the setting of chronic fibrosing ILDs with a progressive phenotype.
Idiopathic pulmonary fibrosis (IPF) is a progressive, chronic fibrotic lung disease with an irreversible decline of lung function. "Bronchiolization", characterized by ectopic appearance of airway ...epithelial cells in the alveolar regions, is one of the characteristic features in the IPF lung. Based on the knowledge that club cells are the major epithelial secretory cells in human small airways, and their major secretory product uteroglobin (SCGB1A1) is significantly increased in both serum and epithelial lining fluid of IPF lung, we hypothesize that human airway club cells contribute to the pathogenesis of IPF. By assessing the transcriptomes of the single cells from human lung of control donors and IPF patients, we identified two SCGB1A1.sup.+ club cell subpopulations, highly expressing MUC5B, a significant genetic risk factor strongly associated with IPF, and SCGB3A2, a marker heterogeneously expressed in the club cells, respectively. Interestingly, the cellular proportion of SCGB1A1.sup.+ MUC5B.sup.+ club cells was significantly increased in IPF patients, and this club cell subpopulation highly expressed genes related to mucous production and immune cell chemotaxis. In contrast, though the cellular proportion did not change, the molecular phenotype of the SCGB1A1.sup.+ SCGB3A2.sup.high club cell subpopulation was significantly altered in IPF lung, with increased expression of mucins, cytokine and extracellular matrix genes. The single cell transcriptomic analysis reveals the cellular and molecular heterogeneity of club cells, and provide novel insights into the biological functions of club cells in the pathogenesis of IPF.
Chronic obstructive pulmonary disease (COPD) is a heterogeneous smoking-related disease characterized by airway obstruction and inflammation. This inflammation may persist even after smoking ...cessation and responds variably to corticosteroids. Personalizing treatment to biologically similar "molecular phenotypes" may improve therapeutic efficacy in COPD. IL-17A is involved in neutrophilic inflammation and corticosteroid resistance, and thus may be particularly important in a COPD molecular phenotype.
We generated a gene expression signature of IL-17A response in bronchial airway epithelial brushings from smokers with and without COPD (n = 238), and validated it using data from 2 randomized trials of IL-17 blockade in psoriasis. This IL-17 signature was related to clinical and pathologic characteristics in 2 additional human studies of COPD: (a) SPIROMICS (n = 47), which included former and current smokers with COPD, and (b) GLUCOLD (n = 79), in which COPD participants were randomized to placebo or corticosteroids.
The IL-17 signature was associated with an inflammatory profile characteristic of an IL-17 response, including increased airway neutrophils and macrophages. In SPIROMICS the signature was associated with increased airway obstruction and functional small airways disease on quantitative chest CT. In GLUCOLD the signature was associated with decreased response to corticosteroids, irrespective of airway eosinophilic or type 2 inflammation.
These data suggest that a gene signature of IL-17 airway epithelial response distinguishes a biologically, radiographically, and clinically distinct COPD subgroup that may benefit from personalized therapy.
ClinicalTrials.gov NCT01969344.
Primary support from the NIH, grants K23HL123778, K12HL11999, U19AI077439, DK072517, U01HL137880, K24HL137013 and R01HL121774 and contracts HHSN268200900013C, HHSN268200900014C, HHSN268200900015C, HHSN268200900016C, HHSN268200900017C, HHSN268200900018C, HHSN268200900019C and HHSN268200900020C.
While asthma is considered an inflammatory-mediated airway epithelial and smooth muscle disorder, there is increasing evidence of airway capillary endothelial dysfunction associated with vascular ...remodelling and angiogenesis in some individuals with this condition. The inflammation is typically characterized as type-2 high (eosinophilic) vs type 2-low (neutrophilic and pauci-granulocytic); we hypothesized that the type-2 high group would be more likely to evidence endothelial dysfunction. As a biomarker of these processes, we hypothesized that nonsmokers with allergic asthma may have elevated plasma levels of endothelial microparticles (EMPs), membrane vesicles that are shed when endothelial cells undergo activation or apoptosis. Total and apoptotic circulating EMPs were measured by fluorescence-activated cell analysis in patients with allergic asthma (n = 29) and control subjects (n = 26), all nonsmokers. When the entire group of patients with asthma were compared to the control subjects, there were no differences in total circulating EMPs nor apoptotic EMPs. However, patients with asthma with elevated levels of IgE and eosinophils had higher levels of apoptotic EMPs, compared to patients with asthma with mildly increased IgE and eosinophil levels. This observation is relevant to precision therapies for asthma and highlights the importance of sub-phenotyping in the condition.
Little is known about human club cells, dome-shaped cells with dense cytoplasmic granules and microvilli that represent the major secretory cells of the human small airways (at least sixth-generation ...bronchi).
To define the ontogeny and biology of the human small airway epithelium club cell.
The small airway epithelium was sampled from the normal human lung by bronchoscopy and brushing. Single-cell transcriptome analysis and air-liquid interface culture were used to assess club cell ontogeny and biology.
We identified the club cell population by unbiased clustering using single-cell transcriptome sequencing. Principal component gradient analysis uncovered an ontologic link between KRT5 (keratin 5)
basal cells and SCGB1A1 (secretoglobin family 1A member 1)
club cells, a hypothesis verified by demonstrating in vitro that a pure population of human KRT5
SCGB1A1
small airway epithelial basal cells differentiate into SCGB1A1
KRT5
club cells on air-liquid interface culture. Using SCGB1A1 as the marker of club cells, the single-cell analysis identified novel roles for these cells in host defense, xenobiotic metabolism, antiprotease, physical barrier function, monogenic lung disorders, and receptors for human viruses.
These observations provide novel insights into the molecular phenotype and biologic functions of the human club cell population and identify basal cells as the human progenitor cells for club cells.
Idiopathic pulmonary fibrosis (IPF) is a progressive disease with a variable clinical course and high mortality. We used data from a large national US registry of patients with IPF to investigate ...relationships between patient characteristics, including markers of disease severity, and mortality.
The analysis cohort comprised patients enrolled in the IPF-PRO Registry from its inception on 5 June 2014 to 26 October 2017. The primary criterion for inclusion in this registry is that patients must be diagnosed or confirmed with IPF at the enrolling centre within 6 months. Associations between patient characteristics and markers of disease severity at enrolment and mortality outcomes were investigated using univariable, multivariable and adjustment models.
Among 662 patients enrolled, 111 patients died or had a lung transplant over a follow-up period of 30 months. The probability of being free of both events at month 30 was 50.6% (95% CI: 40.0, 60.2). When patient characteristics and markers of disease severity were jointly examined in a multivariable analysis, oxygen use at rest (hazard ratio HR 2.44 95% CI: 1.45, 4.10), lower forced vital capacity (FVC) % predicted (HR 1.28 95% CI: 1.10, 1.49 per 10% decrease) and diffusion capacity for carbon monoxide (DLco) % predicted (HR 1.25 95% CI: 1.04, 1.51 per 10% decrease) were significantly associated with increased risk of death or lung transplant. The risk of death or lung transplant increased with increasing age in patients ≥62 years old (HR 1.18 95% CI: 0.99, 1.40 per 5-year increase), and decreased with increasing age in patients <62 years old (HR 0.60 95% CI: 0.39, 0.92 per 5-year increase).
In an observational US registry of patients with IPF, oxygen use at rest, lower FVC % predicted, and lower DLco % predicted were associated with risk of death or lung transplant. An audio podcast of the lead author discussing these data can be downloaded from: http://www.usscicomms.com/respiratory/snyder/IPF-PROsurvival1/ .
ClinicalTrials.gov number: NCT01915511 .
Lysyl oxidase-like 2 (LOXL2) catalyses collagen cross-linking and is implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). The aim of this study was to investigate the efficacy and ...safety of simtuzumab, a monoclonal antibody against LOXL2, in patients with IPF.
In this randomised, double-blind, phase 2 trial, we recruited patients aged 45-85 years with definite IPF diagnosed prior to 3 years of screening from 183 hospitals and respiratory clinics in 14 countries. Eligible patients, stratified by baseline forced vital capacity (FVC), serum LOXL2 (sLOXL2) concentrations, and pirfenidone and nintedanib use, were randomly assigned (1:1) to inject 125 mg/mL simtuzumab or placebo subcutaneously once a week. The primary endpoints were progression-free survival, defined as time to all-cause death or a categorical decrease from baseline in FVC % predicted, in the intention-to-treat population, in patients with sLOXL2 concentrations in the 50th percentile or higher, and in patients with sLOXL2 concentrations in the 75th percentile or higher. Treatment duration was event-driven, and interim analyses were planned and conducted after approximately 120 and 200 progression-free survival events, respectively, occurred. We compared treatment groups with the stratified log-rank test. This study is registered with ClinicalTrials.gov, number NCT01769196.
Patients with IPF were recruited between Jan 31, 2013, and June 1, 2015. The intention-to-treat population included 544 randomly assigned patients (272 patients in both groups), and the safety population included 543 randomly assigned patients who received at least one dose of study medication. The study was terminated when the second interim analysis met the prespecified futility stopping criteria in the intention-to-treat population. We noted no difference in progression-free survival between simtuzumab and placebo in the intention-to-treat population (median progression free survival times of 12·6 months and 15·4 months for simtuzumab and placebo, respectively; stratified HR 1·13, 95% CI 0·88-1·45; p=0·329) and in patients with baseline sLOXL2 in the 50th percentile or higher (median progression-free survival 11·7 months and 14·3 months for simtuzumab and placebo, respectively; stratified HR 1·03, 95% CI 0·74-1·43; p=0·851), or in the 75th percentile or higher (median progression-free survival 11·6 months and 16·9 months for simtuzumab and placebo, respectively; stratified HR 1·20, 95% CI 0·72-2·00; p=0·475). The incidence of adverse events and serious adverse events was similar between treatment groups. The most common adverse events in both the simtuzumab and placebo groups were dyspnoea, cough, upper respiratory tract infection, and worsening of IPF; and the most common grade 3 or 4 adverse events were worsening of IPF, dyspnoea, and pneumonia.
Simtuzumab did not improve progression-free survival in a well-defined population of patients with IPF. Our data do not support the use of simtuzumab for patients with IPF.
Gilead Sciences Inc.