Markers Of Neutrophilic Inflammation Research Articles

Changes in urinary glutathione sulfonamide (GSA) levels between admission and discharge of patients with cystic fibrosis

There is an urgent need to develop sensitive, non-invasive biomarkers that can track airway inflammatory activity for patients with cystic fibrosis (CF). Urinary glutathione sulfonamide (GSA) levels correlate well with GSA levels in BAL samples and other markers of neutrophilic inflammation, suggesting that this biomarker may be suitable for tracking disease activity in this population. We recruited 102 children (median 11.5 years-old) and 64 adults (median 32.5 years-old) who were admitted to hospital for management of an acute pulmonary exacerbation and/or eradication of infectious agents such as Pseudomonas aeruginosa or Staphylococcus aureus. Our aim was to explore how urinary GSA levels changed across admission timepoints. Urine samples were collected at admission and discharge, and GSA measured by liquid chromatography with mass spectrometry. Paired admission-discharge results were compared using Wilcoxon signed-rank test. Paired admission-discharge samples were available for 53 children and 60 adults. A statistically significant difference was observed between admission-discharge for children and adults. Spearman's correlation analysis identified a correlation between urinary GSA levels and sex and S. aureus infection for children only. Our preliminary findings suggest that urinary GSA is responsive to the resolution of an acute pulmonary exacerbation and therefore warrants further studies in this population.

Aspergillus Infections and Progression of Structural Lung Disease in Children with Cystic Fibrosis.

Rationale: Recent data show that Aspergillus species are prevalent respiratory infections in children with cystic fibrosis (CF). The biological significance of these infections is unknown.Objectives: We aimed to evaluate longitudinal associations between Aspergillus infections and lung disease in young children with CF.Methods: Longitudinal data on 330 children participating in the Australian Respiratory Early Surveillance Team for Cystic Fibrosis surveillance program between 2000 and 2018 who underwent annual chest computed tomography (CT) imaging and BAL were used to determine the association between Aspergillus infections and the progression of structural lung disease. Results were adjusted for the effects of other common infections, associated variables, and repeated visits. Secondary outcomes included inflammatory markers in BAL, respiratory symptoms, and admissions for exacerbations.Measurements and Main Results:Haemophilus influenzae, Staphylococcus aureus, Pseudomonas aeruginosa, and Aspergillus infections were all associated with worse CT scores in the same year (Poverall < 0.05). Only P. aeruginosa and Aspergillus were associated with progression in CT scores in the year after an infection and worse CT scores at the end of the observation period. P. aeruginosa was most significantly associated with development of bronchiectasis (difference, 0.9; 95% confidence interval, 0.3-1.6; P = 0.003) and Aspergillus with trapped air (difference, 3.2; 95% confidence interval, 1.0-5.4; P = 0.004). Aspergillus infections were also associated with markers of neutrophilic inflammation (P < 0.001) and respiratory admissions risk (P = 0.008).Conclusions: Lower respiratory Aspergillus infections are associated with the progression of structural lung disease in young children with CF. This study highlights the need to further evaluate early Aspergillus species infections and the feasibility, risk, and benefit of eradication regimens.

Sputum cell IL-1 receptor expression level is a marker of airway neutrophilia and airflow obstruction in asthmatic patients

Various clinical, biologic, or physiologic markers of asthma have been used to identify patient clusters and potential targets for therapy. However, these identifiers frequently overlap among the different asthma groups. For instance, both eosinophil and neutrophil counts are often increased in the airways of asthmatic patients despite their typical association with type 2 and type 17 immune response, respectively. We sought to determine whether inflammatory gene expression is related to patterns of airway inflammation and lung function and identify molecular markers for neutrophilic asthma. Expression levels of 17 genes characterizing type 1, type 2, and type 17 lymphocytes were measured in sputum samples from 48 participants with asthma. The relationships between gene expression levels and sputum cell differentials or measures of pulmonary function were examined by using partial least squares regression. Gene expression levels were strongly associated with cell differentials, explaining 71% of variation in eosinophil counts and 64% of variation in neutrophil counts. The 3 genes with the strongest relationships to sputum neutrophil counts were IL1R1 (standardized regression coefficient [β]=+0.27, P=.005), IL1RAP (β=+0.32, P=.0004), and IL4R (β=+0.29, P=.002). Higher expression levels of IL1R1, IL1RAP, and IL4R were associated with reduced FEV1/forced vital capacity ratio (β=-0.11, -0.08, and -0.10; P=.005, .07, and .05). IL-1 receptor appears to be a marker of neutrophilic inflammation and airflow obstruction in patients with asthma, who have a wide range of disease severity. The IL-1 pathway might contribute to airway neutrophilia and is a potential therapeutic target in patients with neutrophilic asthma.

456 - Glutathione Deficiency and Neutrophil-Mediated Oxidative Stress in the Lungs of Young Children with Cystic Fibrosis

Background Despite limited evidence from studies in humans, the concentration of the antioxidant glutathione is widely considered to be low in the epithelial lining fluid (ELF) from patients with cystic fibrosis (CF) and extensive therapeutic efforts are put into restoring glutathione levels. However, to date it remains unclear, whether glutathione deficiency is an inherent defect in CF that occurs early in life, whether depletion of reduced glutathione is caused by neutrophil-mediated oxidative stress in the airways, and whether low glutathione is associated with bronchiectasis. Methods Using LC/MS, we measured glutathione (GSH), oxidized glutathione (GSSG), glutathione attached to proteins (GSSP) and glutathione sulfonamide (GSA) in BAL from 586 infants and children with CF and 63 without (ages 0.2-15.5 yr.). Levels of glutathione species were related to infection status, bronchiectasis data from chest computed tomography (CT) scans, markers of neutrophilic inflammation, neutrophil elastase (NE) and Il-8; and neutrophil-mediated oxidative stress, myeloperoxidase (MPO) and oxidized uric acid (allantoin). Results Glutathione levels were low in the lungs of individuals with CF from an early age irrespective of oxidation. GSH was decreased in children with infections; while oxidized glutathione species were elevated and related to other markers of neutrophil-related inflammation and oxidative stress. GSSP, MPO and NE, but not GSH, GSSG and GSA, were associated with bronchiectasis. Conclusions Airway glutathione is low in cystic fibrosis from a young age while marked neutrophil-mediated oxidation is present in the lung. Neutrophils promote a worse disease outcome both via oxidative modification of proteins and the release of NE highlighting the need to target both NE and MPO. At the same time, more research is needed into effective delivery of glutathione to sites of inflammation at a young age.

A Randomized, Placebo-controlled Trial of Roflumilast. Effect on Proline-Glycine-Proline and Neutrophilic Inflammation in Chronic Obstructive Pulmonary Disease.

Roflumilast is a therapeutic agent in the treatment of chronic obstructive pulmonary disease (COPD). It has antiinflammatory effects; however, it is not known whether it can affect a biologic pathway implicated in COPD pathogenesis and progression. The self-propagating acetyl-proline-glycine-proline (AcPGP) pathway is a novel means of neutrophilic inflammation that is pathologic in the development of COPD. AcPGP is produced by extracellular matrix collagen breakdown with prolyl endopeptidase and leukotriene A4 hydrolase serving as the enzymes responsible for its production and degradation, respectively. We hypothesized that roflumilast would decrease AcPGP, halting the feed-forward cycle of inflammation. We conducted a single-center, placebo-controlled, randomized study investigating 12 weeks of roflumilast treatment added to current therapy in moderate-to-severe COPD with chronic bronchitis. Subjects underwent sputum and blood analyses, pulmonary function testing, exercise tolerance, and quality-of-life assessment at 0, 4, and 12 weeks. Twenty-seven patients were enrolled in the intention-to-treat analysis. Roflumilast treatment decreased sputum AcPGP by more than 50% (P < 0.01) and prolyl endopeptidase by 46% (P = 0.02), without significant improvement in leukotriene A4 hydrolase activity compared with placebo. Roflumilast also reduces other inflammatory markers. There were no significant changes in lung function, quality of life, or exercise tolerance between roflumilast- and placebo-treated groups. Roflumilast reduces pulmonary inflammation through decreasing prolyl endopeptidase activity and AcPGP. As expected for lower AcPGP levels, markers of neutrophilic inflammation are blunted. Inhibiting this self-propagating pathway lessens the overall inflammatory burden, which may alter the natural history of COPD, including the risk of exacerbation. Clinical trial registered with www.clinicaltrials.gov (NCT 01572948).

Potential prognostic value of biomarkers in lavage, sputum and serum in a five year clinical follow-up of smokers with and without COPD

BackgroundThe aim of this study was to test whether repeatable biomarkers collected from serum, bronchoalveolar lavage (BAL) and sputum of healthy smokers and smokers with COPD would have a prognostic value with respect to the decline in lung function over a 5 year period.MethodsIn 2006/2007 we had repeatedly collected serum, BAL and sputum of 23 healthy smokers and 24 smokers with COPD (GOLD II) and analysed a panel of more than 100 different parameters. In 2012 we reinvited these subjects to assess the change in lung function to enable the investigation of the potential prognostic value of the 2006/2007 markers and to determine the long-term repeatability of selected blood and serum markers. In this follow-up study we performed body-plethysmography, a blood gas analysis and collected blood and urine samples. The change in lung function was compared with 67 markers from BAL, sputum, serum and whole blood that were shown in the 2006/2007 assessment to be repeatable over a 6 week period.ResultsWe were able to recruit 13 (54%) smokers with COPD and 11 (48%) former healthy smokers that participated in the 2006/2007 study. The decline in lung function was larger in COPD smokers; five of them changed to GOLD III, one to GOLD IV. Two healthy smokers changed to GOLD I. Blood cells, serum von Willebrand factor and alpha-1-antitrypsin showed a good repeatability over 5 years. In COPD smokers a weak correlation between 2006/2007 sputum markers of neutrophilic inflammation and the 5 year change in FEV1/FVC was found.ConclusionsOur data suggests that inter-individual and group differences are maintained over a five year period. Despite the large panel of markers available for this analysis, a potential prognostic value appears to exist only for some sputum inflammatory markers. If these data can be confirmed in larger COPD cohorts, it would emphasize the value of sputum markers in clinical trials and support the assumption that an anti-inflammatory treatment can have long term benefits in COPD.

Progranulin is a substrate for neutrophil-elastase and proteinase-3 in the airway and its concentration correlates with mediators of airway inflammation in COPD

Progranulin (PGRN) is an anti-inflammatory protein, yet its digestion by neutrophil-derived proteinases generates products that can stimulate epithelial cell lines to secrete the neutrophil chemoattractant interleukin (IL)-8. Because dysregulated neutrophilic inflammation is implicated in the pathophysiology of chronic obstructive pulmonary disease (COPD), the possible influence of PGRN and digestion products may be of relevance to understanding and treating inflammation in the disease. PGRN was measured in sputum sol-phase samples from patients with a clinical diagnosis of COPD and chronic sputum production in a clinically stable state; PGRN correlated negatively with bacterial load (colony-forming units/ml) (r = -0.446, P = 0.003, n = 43) and markers of neutrophilic inflammation, including neutrophil elastase (NE, nM) (r = -0.562, P = 0.008, n = 21) and proteinase-3 (PR3, nM) (r = -0.515, P = 0.017, n = 21). Products of PGRN digestion were detected in sputum sol phase, and PGRN conversion activity in sputum sol phase was inhibited with the serine proteinase inhibitor α1-antitrypsin. Digested PGRN at concentrations likely to be present in the airways did not stimulate IL-8 secretion from normal human bronchial epithelial (NHBE) cells. Infection of NHBE cells with live Haemophilus influenzae significantly increased PGRN secretion compared with untreated cells (P ≤ 0.001). The concentration of PGRN relates negatively to the amplified airway inflammation associated with bacterial colonization in clinically stable COPD. This relationship is driven by the proteolytic action of the neutrophil-derived proteinases NE and PR3; the products released by this action are unlikely to stimulate significant IL-8 secretion from epithelial cells in the airways.

Functional heterogeneity of pulmonary surfactant protein-D in cystic fibrosis

Pulmonary surfactant protein-D (SP-D) is a soluble collagenous C-type lectin with important anti-microbial and anti-inflammatory properties. Although it is subject to functionally relevant modification by common polymorphisms and unregulated inflammation, the functional status of SP-D in cystic fibrosis (CF) remains unclear. Given the importance of infection and inflammation in CF lung pathology we have undertaken the first systematic analysis of SP-D lectin activity in this population. By ELISA, we found that airway lavage fluid SP-D expression was greater in CF compared to control patients but was reduced in CF patients with infection and correlated negatively with markers of neutrophilic inflammation. In a functional assay, the percentage of SP-D capable of binding zymosan rarely exceeded 60% in CF or control patients and similarly restricted binding activity was observed towards maltose–agarose. SP-D lectin activity also correlated negatively with infection and neutrophilic inflammation but there was little evidence of major proteolytic degradation amongst the non-bound material. SP-D which failed to bind zymosan exhibited features of lower oligomeric form compared to bound material when tested by native gel electrophoresis. Furthermore, when separated by gel chromatography, high and low oligomeric populations of SP-D were observed in CF lavage fluid but only high oligomeric forms exhibited substantial lectin activity towards yeast derived mannan. Our data demonstrate that oligomeric heterogeneity underlies functional diversity amongst SP-D in health and disease and that dynamic regulation of oligomerisation is an important feature of SP-D biology.

Sputum and serum hydrogen sulfide (H2S) as novel biomarker of asthma

Hydrogen sulfide (H2S) is a gas produced by respiratory cells including smooth muscle cells and may play a role as a gasotransmitter. We determined whether H2S levels in serum or sputum supernatants could represent a biomaker of asthma. We measured H2S in induced sputum and serum samples of patients with severe and non-severe asthma and of healthy subjects. H2S concentrations were measured using a sulfide-sensitive electrode. H2S levels in induced sputum from severe and non-severe asthmatic patients were significantly higher than those from healthy subjects but there was no difference between the severe and non-severe group. Serum H2S levels were 10 times higher than in sputum and these were also higher in severe and non-severe asthmatic subjects compared to healthy subjects. There was a positive correlation between sputum and blood H2S levels (r=0.42, p<0.05). Sputum H2S levels were negatively correlated with FEV1 %predicted (r=-0.42, p=0.003), and with reversibility to salbutamol (r= -0.54, p<0.01). There was a correlation between sputum H2S and sputum neutrophils and macrophages, and a negative correlation between sputum H2S and FeNO levels. Endogenous H2S, measured in induced sputum, may be a marker of neutrophilic inflammation and bronchial narrowing.

Proteomic Analysis of Human Bronchoalveolar Lavage Fluid after Subsgemental Exposure

The analysis of airway fluid, as sampled by bronchoalveolar lavage (BAL), provides a minimally invasive route to interrogate lung biology in health and disease. Here, we used immunodepletion, coupled with gel- and label-free LC-MS/MS, for quantitation of the BAL fluid (BALF) proteome in samples recovered from human subjects following bronchoscopic instillation of saline, lipopolysaccharide (LPS) or house dust mite antigen into three distinct lung subsegments. Among more than 200 unique proteins quantified across nine samples, neutrophil granule-derived and acute phase proteins were most highly enriched in the LPS-exposed lobes. Of these, peptidoglycan response protein 1 was validated and confirmed as a novel marker of neutrophilic inflammation. Compared to a prior transcriptomic analysis of airway cells in this same cohort, the BALF proteome revealed a novel set of response factors. Independent of exposure, the enrichment of tracheal-expressed proteins in right lower lung lobes suggests a potential for constitutive intralobar variability in the BALF proteome; sampling of multiple lung subsegments also appears to aid in the identification of protein signatures that differentiate individuals at baseline. Collectively, this proof-of-concept study validates a robust workflow for BALF proteomics and demonstrates the complementary nature of proteomic and genomic techniques for investigating airway (patho)physiology.

Influence of Age, Past Smoking, and Disease Severity on TLR2, Neutrophilic Inflammation, and MMP-9 Levels in COPD

Chronic obstructive pulmonary disease (COPD) is a common and serious respiratory disease, particularly in older individuals, characterised by fixed airway obstruction and persistent airway neutrophilia. The mechanisms that lead to these features are not well established. We investigated the contribution of age, prior smoking, and fixed airflow obstruction on sputum neutrophils, TLR2 expression, and markers of neutrophilic inflammation. Induced sputum from adults with COPD (n = 69) and healthy controls (n = 51) was examined. A sputum portion was dispersed, total, differential cell count and viability recorded, and supernatant assayed for CXCL8, matrix metalloproteinase- (MMP-) 9, neutrophil elastase, and soluble TLR2. Peripheral blood cells (n = 7) were stimulated and TLR2 activation examined. TLR2 levels were increased with ageing, while sputum neutrophils and total sputum MMP-9 levels increased with age, previous smoking, and COPD. In multivariate regression, TLR2 gene expression and MMP-9 levels were significant independent contributors to the proportion of sputum neutrophils after adjustment for age, prior smoking, and the presence of airflow obstruction. TLR2 stimulation led to enhanced release of MMP-9 from peripheral blood granulocytes. TLR2 stimulation activates neutrophils for MMP-9 release. Efforts to understand the mechanisms of TLR2 signalling and subsequent MMP-9 production in COPD may assist in understanding neutrophilic inflammation in COPD.

The basic markers of neutrophilic inflammation in severe bronchial asthma (the literature review)

In spite of the marked insights of modern medicine into the pathogenesis of bronchial asthma, there is unresolved issue regarding achievement of therapeutic control. Understanding of the immunopathogenesis of the disease resulted in a subdivision into different biological phenotypes due to dominating inflammatory component, characterized by list of biological markers. A role of neutrophilic inflammation in bronchial asthma has been widely discussed in recent studies but is still uncertain. In general, asthma associated with neutrophils tends to be a more aggressive disease with more tissue destruction and airway remodeling; tightly associated with lower response to corticosteroids treatment, moreover, it could be induced by it.

Proteinase 3 activity in sputum from subjects with alpha-1-antitrypsin deficiency and COPD

Chronic obstructive pulmonary disease (COPD) is associated with tissue damage believed to result from an imbalance between serine proteinases and their inhibitors. Although the role of neutrophil elastase (NE) has been studied, it is likely that other proteinases play a role. The importance of proteinase 3 (PR3) has not been established, as specific substrates have only recently been available. We studied clinically stable subjects with either alpha-1-antitrypsin (A1AT) deficiency or usual COPD with chronic bronchitis. Sol phase sputum was analysed for PR3 activity and concentration, NE activity and concentration, concentrations of airway inhibitors (A1AT, secretory leukoproteinase inhibitor and elafin) and markers of neutrophilic inflammation. 12 patients were also studied during exacerbations. PR3 activity was present in most sputum samples and greater than NE activity (which was largely undetectable) in both subject groups (A1AT deficiency median PR3 128 nM, interquartile range (IQR) 33-558 nM; NE 0 nM, IQR 0-0 nM; p=0.0043; COPD PR3 22 nM, IQR 0-103 nM; NE 0 nM, IQR 0-0 nM; p=0.015). PR3 activity was greater during exacerbations than in the stable state (p=0.037) and correlated with markers of neutrophilic inflammation. The regular identification of PR3 activity in sputum from stable subjects with A1AT deficiency or usual COPD suggests it may play a greater role in the pathophysiology than previously thought.

Association of exhaled breath condensate pH with markers of neutrophilic inflammation in bronchoalveolar lavage in young children with cystic fibrosis

Association of exhaled breath condensate pH with markers of neutrophilic inflammation in bronchoalveolar lavage in young children with cystic fibrosis

Pulmonary Function Is Negatively Correlated With Sputum Inflammatory Markers and Cough Clearability in Subjects With Cystic Fibrosis But Not Those With Chronic Bronchitis

Polymorphonuclear neutrophil (PMN)-dominated inflammation is prominent in the airways of subjects with cystic fibrosis (CF) and chronic bronchitis (CB). Interleukin (IL)-8, myeloperoxidase (MPO), and DNA are markers of neutrophilic inflammation. We hypothesized that sputum MPO, DNA, and IL-8 concentrations would negatively correlate with pulmonary function and sputum transportability. We measured pulmonary function and analyzed sputum IL-8, MPO, and DNA concentrations, as well as the transport properties of sputum samples obtained from 16 subjects with CF and 15 subjects with CB. We also evaluated changes in these measurements in paired sputum samples from these subjects obtained 2 to 12 months apart. IL-8 and MPO concentrations in the sputum of CF subjects was inversely correlated with FEV(1) percent predicted (IL-8: r = -0.40; p = 0.003; MPO: r = -0.38; p = 0.003) and FVC percent predicted (IL-8: r = -0.4; p = 0.02; MPO: r = -0.4; p = 0.02). IL-8 and DNA concentrations were inversely correlated with sputum cough transportability (CTR) [IL-8: r = -0.4; p = 0.02; DNA: r = -0.36; p = 0.048]. Changes in DNA concentration in sputum samples from CF subjects over time were inversely correlated with changes in FEV(1) percent predicted (r = -0.58; p = 0.02), FVC percent predicted (r = -0.74; p = 0.002), and CTR (r = -0.59; p = 0.02). There was no correlation among pulmonary function, sputum properties, and inflammatory markers in the sputum from subjects with CB. The sputum concentrations of IL-8, MPO, and DNA appear to be closely associated with pulmonary function in subjects with CF but not in subjects with CB.

Inhaled corticosteroid effects both eosinophilic and non‐eosinophilic inflammation in asthmatic patients

AIM: To determine induced sputum cell counts and interleukin-8 (IL-8), tumor necrosis factor alpha (TNF-alpha) and leukotriene B4 (LTB4) levels as markers of neutrophilic inflammation in moderate persistent asthma, and to evaluate the response to inhaled steroid therapy. METHODS: Forty-five moderate asthmatic patients and 10 non-smoker controls were included in this study. All patients received inhaled corticosteroid (800 microg of budesonide) for 12 weeks. Before and after treatment pulmonary function tests were performed, and symptom scores were determined. Blood was drawn for analysis of serum inflammatory markers, and sputum was induced. RESULTS: Induced sputum cell counts and inflammatory markers were significantly higher in patients with asthma than in the control group. The induced sputum eosinophil counts of 12 patients (26%) were found to be less than 5%, the non-eosinophilic group, and sputum neutrophil counts, IL-8 and TNF-alpha levels were significantly higher than the eosinophilic group (neutrophil, 50+/-14% versus 19+/-10%, p<0.01). In both groups, there was a significant decrease in sputum total cell counts and serum and sputum IL-8, TNF-alpha and LTB4 levels after the treatment. There was no change in sputum neutrophil counts. Although the sputum eosinophil count decreased only in the eosinophilic subjects, there was no significant difference in inflammatory markers between the groups. The symptom scores were significantly improved after treatment, while the improvement did not reach statistical significance on pulmonary function test parameters. CONCLUSION: Notably, in chronic asthma there is a subgroup of patients whose predominant inflammatory cells are not eosinophils. Sputum neutrophil counts and neutrophilic inflammatory markers are significantly higher in these patients. In the non-eosinophilic group, inhaled steroid caused an important decrease in inflammatory markers; however, there was no change in the sputum eosinophil and neutrophil counts.