Sputum Neutrophils Research Articles

Biologics in asthma management - Are we out of breath yet?

The biologics authorized for the add-on therapy of severe asthma are monoclonal antibodies (mAbs). Before they are considered for therapy intensification, the patient’s asthma endotype is determined on the basis of phenotypic characteristics. So far, 5 biologics are available that target the signaling pathways of the “TH2-high” asthma endotype, in which cytokines of the inflammation cascade mediated by type 2 T-helper cells are upregulated. The corresponding phenotype of this inflammatory endotype is severe eosinophilic asthma, with elevated eosinophils, immunoglobulin E, and fractional exhaled nitric oxide (FeNO). In contrast, the heterogeneous “TH2-low” endotype is not yet sufficiently understood. Frequently described in this variant is an increase of sputum neutrophils and an increased expression of the TH17-mediated interleukin-17 signaling pathway. There are numerous biologics currently in clinical trials, the thymic stromal lymphopoietin (TSLP) mAbs in particular have shown promising results independent of the asthma phenotype.

Role of neutrophils and bronchial epithelium in loss of control of bronchial asthma and formation of respiratory tract response to cold stimulus

Introduction . Neutrophils and bronchial epithelium are actively involved in the generation of oxidative stress and the progression of airway inflammation in patients with asthma. Aim . To study the role of neutrophils and bronchial epithelium as factors contributing to the loss of control over asthma and the formation of the airway response to a cold stimulus. Materials and methods . A total of 146 patients with a diagnosis of persistent asthma were examined. A survey was conducted on the Asthma Control Test (ACT) questionnaire; a study of the lung function by spirometry with subsequent collection of induced sputum; the next day, a 3-minute isocapnic hyperventilation by cold (-20ºC) air (IHCA) was performed, followed by collection of spontaneously produced sputum. In the sputum, cytosis, cellular composition, and glycoprotein concentration in the goblet-like epithelium were assessed. Group 1 (n=89) included persons with uncontrolled (ACT˂20 points), group 2 (n=57) – with controlled (ACT>20 points) asthma. Results . Patients of group 1 in comparison with group 2 had a higher increase in FEV 1 to the inhalation of a short-acting β 2 -agonist ‒ 11.0 (5.4; 21.65) vs. 7.55 (4.11; 13.8)%, respectively (p=0.042) and a more pronounced reaction to the IHCA test ‒ -11.0 (-17.6; -2.5) vs. -6.0 (-12.0; - 2.0)% (p=0.031). In patients of group 1, after the IHCA test, an increase in the number of neutrophils was observed from 45.98±2.17 to 52.0±1.78% (p=0.0013) and an increase in the concentration of glycoproteins in mucocytes from 37.9±3.8 to 45.6±4.2% (p=0.002) against the background of a tendency towards an increase in the concentration of goblet cells and a decrease in the number of intact bronchial epithelial cells (from 4.8±0.32 to 3.9±0.30%; p=0.017). Correlation analysis showed the relationship between the level of goblet cell glycoproteins and the initial concentration of neutrophils in sputum (r=-0.49; p=0.039), as well as between the severity of the reaction of the distal bronchi (ΔMEF 50 ) to a cold stimulus and the concentration of neutrophils in sputum after IHCA (r=0.36; p=0.01). Conclusion . The signs of stimulation of the neutrophilic segment of granulocytes and structural rearrangement of the bronchial epithelium in the sputum of patients with uncontrolled asthma after acute cold exposure were determined. Structural changes in the pool of neutrophils and epithelial parenchyma of the bronchi, indicating an escalation of pro-inflammatory activity, may underlie the emergence and maintenance of the airway response to a cold stimulus and loss of asthma control.

Hydrolytic enzymes of airway neutrophilic granulocytes in patients with asthma under cold stimuli exposure

Introduction . The labilization of lysosomal membranes with the release of a wide range of lysosomal enzymes of pro-inflammatory and proapoptotic action, which have a high hydrolytic potential, is one of the essential components of adaptive changes in cells under stress. The participation of hydrolytic enzymes of phagocytes in cellular reactions of inflammation and adaptation to cold stress in patients with asthma has been little studied. Aim . To study the activity of neutrophil hydrolases of bronchi in patients with asthma under cold-induced stress. Materials and methods. In patients with persistent asthma (n=13), lung function (FEV 1 ,%), airway response (∆FEV 1 IHCA ,%) to standard 3-minute isocapnic hyperventilation with cold air (IHCA) were determined by spirometry. The collection of induced and spontaneously produced sputum after the IHCA was carried out. The activity of acidic (AP) and alkaline (ALP) phosphatases, adenosine triphosphatase (ATPase) was detected in sputum neutrophils by cytochemical methods. The assessment of the reaction to the activity of hydrolases was carried out by the semi-quantitative Kaplow method with the distribution of cells into groups depending on the color intensity of the product formed during the interaction of the enzyme with the substrate, and the subsequent calculation of the average cytochemical index (ACI) of the enzymatic activity. Results . The baseline FEV 1 , averaged 97.9±5.3%, ∆FEV 1 IHCA -2.0 (-8.0; 2.0)%. Under the influence of a cold stimulus against the background of a mixed pattern of bronchial inflammation in patients, the following was recorded: an increase in the ACI AP of neutrophils (from 1.11±0.06 to 1.42±0.06; p˂0.01), an increase in the number of cells with an average degree of AP activity (from 23.4±1.94 to 40.1±4.30%; p˂0.01) and a decrease in the number of cells with a negative reaction to AP (from 15.1±3,58 to 5.2±2.78%; p˂0.05), a tendency to an increase in the number of neutrophils with a high degree of ATPase activity (from 3.50±2.70 to 7.22±2.64%) and ALP (from 13.7±4.22 to 15.7±3.46%). Conclusion . The activation of AP of neutrophils under cold-induced stress indicates the possibility of an increase in the acidity of the interstitium, stimulation of damage and vulnerability to cold effects of the desmo-epithelial barrier of the bronchi and is regarded as a criterion for a high risk of cold airway hyperresponsiveness in asthma patients with a mixed inflammation phenotype.

Phase 2 Trial of the DPP-1 Inhibitor Brensocatib in Bronchiectasis

BackgroundPatients with bronchiectasis have frequent exacerbations that are thought to be related to neutrophilic inflammation. The activity and quantity of neutrophil serine proteases, including neutrophil elastase, are increased in the sputum of patients with bronchiectasis at baseline and increase further during exacerbations. Brensocatib (INS1007) is an oral reversible inhibitor of dipeptidyl peptidase 1 (DPP-1), an enzyme responsible for the activation of neutrophil serine proteases.MethodsIn a phase 2, randomized, double-blind, placebo-controlled trial, we randomly assigned, in a 1:1:1 ratio, patients with bronchiectasis who had had at least two exacerbations in the previous year to receive placebo, 10 mg of brensocatib, or 25 mg of brensocatib once daily for 24 weeks. The time to the first exacerbation (primary end point), the rate of exacerbations (secondary end point), sputum neutrophil elastase activity, and safety were assessed.ResultsOf 256 patients, 87 were assigned to receive placebo, 82 to receive 10 mg of brensocatib, and 87 to receive 25 mg of brensocatib. The 25th percentile of the time to the first exacerbation was 67 days in the placebo group, 134 days in the 10-mg brensocatib group, and 96 days in the 25-mg brensocatib group. Brensocatib treatment prolonged the time to the first exacerbation as compared with placebo (P=0.03 for 10-mg brensocatib vs. placebo; P=0.04 for 25-mg brensocatib vs. placebo). The adjusted hazard ratio for exacerbation in the comparison of brensocatib with placebo was 0.58 (95% confidence interval [CI], 0.35 to 0.95) in the 10-mg group (P=0.03) and 0.62 (95% CI, 0.38 to 0.99) in the 25-mg group (P=0.046). The incidence-rate ratio was 0.64 (95% CI, 0.42 to 0.98) in the 10-mg group, as compared with placebo (P=0.04), and 0.75 (95% CI, 0.50 to 1.13) in the 25-mg group, as compared with placebo (P=0.17). With both brensocatib doses, sputum neutrophil elastase activity was reduced from baseline over the 24-week treatment period. The incidence of dental and skin adverse events of special interest was higher with the 10-mg and 25-mg brensocatib doses, respectively, than with placebo.ConclusionsIn this 24-week trial, reduction of neutrophil serine protease activity with brensocatib in patients with bronchiectasis was associated with improvements in bronchiectasis clinical outcomes. (Funded by Insmed; WILLOW ClinicalTrials.gov number, NCT03218917.)

Clinical and biological factors associated with irreversible airway obstruction in adult asthma

Background and objectiveAirway remodeling, as many other factors, may lead to lung function decline and irreversible airflow obstruction (IRAO) in asthma. This study was undertaken in order to highlight predictors of incomplete reversibility of airflow obstruction in adult asthmatics to identify patients with poorer prognosis and improve their care, and decrease morbidity. MethodsA retrospective study was conducted in 973 asthmatics recruited from the University Asthma Clinic of Liege. Patients with IRAO (post-BD FEV1/FVC<0.7 & FEV1<80% predicted) were compared to patients with reversible airway obstruction (RAO) (post-BD FEV1/FVC≥0.7 & FEV1≥80% predicted). TGF-β was measured in sputum supernatant of 85 patients. ResultsSeventeen percent of asthmatics presented with IRAO. These patients were significantly older, more smokers, with a lower proportion of female, a longer disease duration, were more poorly controlled with a lower quality of life. This sub-population of asthmatics also showed more often elevated blood and sputum eosinophils and neutrophils, and higher exacerbation and hospitalisation rates in the previous year. The multivariable analysis revealed male gender, longer disease duration, cigarette smoking, ACQ score, sputum eosinophils and neutrophils, ICS dose and OCS maintenance, BMI, and asthma onset as variables independently linked to IRAO. Total TGF-β levels appeared higher in patients with IRAO (n = 38) compared to patients with RAO (n = 47). ConclusionThese data show that risk factors for IRAO are male gender, smoking, a longer disease duration, uncontrolled asthma, eosinophilic or neutrophilic airway inflammation, lower BMI, and later asthma onset. Moreover, TGF-β levels are higher in IRAO.

Bacteria and sputum inflammatory cell counts; a COPD cohort analysis

BackgroundThere is evidence that bacterial colonisation in chronic obstructive pulmonary disease (COPD) is associated with increased neutrophilic airway inflammation. This study tested the hypothesis that different bacterial phyla and species cause different inflammatory profiles in COPD patients.MethodsSputum was analysed by quantitative polymerase chain reaction (qPCR) to quantify bacterial load and 16S rRNA gene sequencing to identify taxonomic composition. Sputum differential cell counts (DCC) and blood DCC were obtained at baseline and 6 months. Patients were categorised into five groups based on bacterial load defined by genome copies/ml of ≥ 1 × 104, no colonisation and colonisation by Haemophilus influenzae (H. influenzae), Moraxella catarrhalis (M. catarrhalis), Streptococcus pneumoniae (S. pneumoniae), or > 1 potentially pathogenic microorganism (PPM).ResultsWe observed an increase in sputum neutrophil (%), blood neutrophil (%) and neutrophil–lymphocyte ratio (NLR) in patients colonised with H. influenzae (82.6, 67.1, and 3.29 respectively) compared to those without PPM colonisation at baseline (69.5, 63.51 and 2.56 respectively) (p < 0.05 for all analyses), with similar findings at 6 months. The bacterial load of H. influenzae and Haemophilus determined by qPCR and 16s rRNA gene sequencing respectively, and sputum neutrophil % were positively correlated between baseline and 6 months visits (p < 0.0001, 0.0150 and 0.0002 with r = 0.53, 0.33 and 0.44 respectively).ConclusionsThese results demonstrate a subgroup of COPD patients with persistent H. influenzae colonisation that is associated with increased airway and systemic neutrophilic airway inflammation, and less eosinophilic airway inflammation.

RAGE and TLR4 differentially regulate airway hyperresponsiveness: Implications for COPD.

The receptor for advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR4) is implicated in COPD. Although these receptors share common ligands and signalling pathways, it is not known whether they act in concert to drive pathological processes in COPD. We examined the impact of RAGE and/or TLR4 gene deficiency in a mouse model of COPD and also determined whether expression of these receptors correlates with airway neutrophilia and airway hyperresponsiveness (AHR) in COPD patients. We measured airway inflammation and AHR in wild-type, RAGE-/- , TLR4-/- and TLR4-/- RAGE-/- mice following acute exposure to cigarette smoke (CS). We also examined the impact of smoking status on AGER (encodes RAGE) and TLR4 bronchial gene expression in patients with and without COPD. Finally, we determined whether expression of these receptors correlates with airway neutrophilia and AHR in COPD patients. RAGE-/- mice were protected against CS-induced neutrophilia and AHR. In contrast, TLR4-/- mice were not protected against CS-induced neutrophilia and had more severe CS-induced AHR. TLR4-/- RAGE-/- mice were not protected against CS-induced neutrophilia but were partially protected against CS-induced mediator release and AHR. Current smoking was associated with significantly lower AGER and TLR4 expression irrespective of COPD status, possibly reflecting negative feedback regulation. However, consistent with preclinical findings, AGER expression correlated with higher sputum neutrophil counts and more severe AHR in COPD patients. TLR4 expression did not correlate with neutrophilic inflammation or AHR. Inhibition of RAGE but not TLR4 signalling may protect against airway neutrophilia and AHR in COPD.

Safety and efficacy of lenabasum in a phase 2 randomized, placebo-controlled trial in adults with cystic fibrosis

Background. Few therapies specifically address the chronic airway inflammation in cystic fibrosis (CF) that contributes to progressive destruction of lung tissue and loss of lung function. Lenabasum is a cannabinoid type 2 receptor (CB2) agonist that resolves inflammation in a number of in vitro and in vivo models.Methods. A Phase 2 double-blind, randomized, placebo-controlled study assessed the safety and tolerability of lenabasum in adults with CF. Subjects with FEV1% (ppFEV1) ≥40% predicted were randomized to lenabasum 1 or 5 mg or placebo once daily (QD) (Weeks 1–4), then 20 mg QD, 20 mg twice daily (BID) or placebo (Weeks 5–12), with follow-up at Week 16. Pulmonary exacerbations (PEx) were recorded and biomarkers of blood and lung inflammation were measured.Results. Of 89 subjects randomized, 51 lenabasum and 23 placebo-only subjects completed the study. No deaths or serious or severe adverse events (AE) were considered related to lenabasum. Most AEs were mild/moderate, and the most common were PEx, hemoptysis, dry mouth, and upper respiratory infection. Three lenabasum and one placebo-only subjects discontinued the study for a treatment related AE. New PEx were treated with intravenous antibiotics in 4.0% of lenabasum-treated vs. 11.4% of placebo-treated subjects, during Weeks 1–4 and 5.2% compared to 13.0% during Weeks 5–12 (p<0.2). No significant differences in ppFEV1 were observed between treatment groups. Sputum neutrophils, eosinophils, and neutrophil elastase were numerically reduced, and significant (p<0.05) reductions in IL-8 and immunoglobulin G levels occurred with lenabasum.Conclusions. The safety findings of lenabasum, coupled with biomarker data, support further testing in a larger study with a longer duration.

The airway fungal microbiome in asthma.

Fungal involvement in asthma is associated with severe disease. The full spectrum of fungal species in asthma is not well described and is derived largely from insensitive culture techniques. To use high-throughput sequencing to describe the airway mycobiota in asthmatics with and without fungal sensitization and healthy controls; to compare samples representing different airway compartments; to determine whether the mycobiota was influenced by the fungal composition of outdoor air; and to compare findings with clinically relevant outcomes. We amplified the internal transcribed spacer region 2 of the nuclear ribosomal operon to identify the fungal species present. Ninety-seven subjects were recruited and provided sputum (83 asthmatics; 14 healthy subjects), with 29 also undergoing a bronchoscopy. A subset of airway samples were compared with matched outdoor air and mouthwash samples. Two hundred and six taxa at the species level were identified in sputum, most at low relative abundance. Aspergillus fumigatus, Candida albicans and Mycosphaerella tassiana had the highest relative abundances and were the most prevalent species across all subjects. The airway mycobiota consisted of a complex community with high diversity between individuals. Notable shifts in the balance of fungi detected in the lung were associated with asthma status, asthma duration and biomarkers of inflammation. Aspergillus tubingensis, a member of the Aspergillus niger species complex, was most prevalent from bronchoscopic protected brush samples and significantly associated with a low sputum neutrophilia. Cryptococcus pseudolongus, from the Cryptococcus humicola species complex, was more abundant from bronchoscopy samples than sputum, and differentially more abundant in asthma than health. The airway mycobiota was dominated by a relatively small number of species, but was distinct from the oropharyngeal mycobiota and air samples. Members of the A.niger and C.humicola species complexes may play unexpected roles in the pathogenesis of asthma.

Asthma and fixed airflow obstruction: Long-term trajectories suggest distinct endotypes.

Long-term trajectories of asthma with fixed airflow obstruction (FAO) may reveal links to inflammatory endotypes. We investigated whether measures of asthma control and airway inflammation and remodelling differed by long-term FAO status in moderate-to-severe asthma. Adults enrolled in the Difficult Asthma Study assessed initially using serial Asthma Control Questionnaire (ACQ), exacerbation history, spirometry and sputum cytology over 12months, as well as endoscopic bronchial biopsy with airway smooth muscle (ASM) quantification, were revaluated three or more years later with questionnaires and spirometry. FAO was defined as a persistent post-bronchodilator forced expired volume in one second (FEV1 )-to-forced vital capacity ratio below 0.70. Sixty-two participants (mean±SD age 48±11years; 50% female; 75% atopic; asthma duration 24±14years) returned for follow-up assessment (median interval 7.9years; IQR: 5.4-8.8years). Compared to participants without FAO (n=28), those with FAO at baseline and long-term follow-up (n=18) had higher baseline sputum neutrophil content and ASM, and a higher exacerbation frequency that persisted at long-term follow-up. Sputum eosinophils, ACQ and long-term FEV1 decline did not differ. Participants with incident FAO at long-term follow-up (n=16) had higher baseline exacerbation frequency, sputum eosinophil content, higher ACQ scores and greater decline in FEV1 , whereas baseline ASM was similar to those without FAO. In moderate-to-severe asthma, long-term FAO is characterized by neutrophilic sputum inflammation and airway remodelling, but FEV1 decline is similar to those without FAO. Long-term incident FAO is preceded by higher exacerbation frequency, higher sputum eosinophil content and significant FEV1 decline.

Multidimensional Assessment of Asthma Identifies Clinically Relevant Phenotype Overlap: A Cross-Sectional Study

Asthma is a heterogeneous disease with multiple phenotypes; however, the relevance of phenotype overlap remains largely unexplored. To examine the relationship between phenotype overlap and clinical and inflammatory profiles of asthma. In this cross-sectional study, adult participants with stable asthma (n= 522) underwent multidimensional assessments. The 10 most common phenotypes of asthma were defined and then classified into those commonly associated with Type (T) 2 or non-T2 inflammation. Furthermore, phenotype overlap scores (POS), representing the cumulative concomitant phenotypes, were used to analyze its association with clinical and inflammatory asthmatic profiles. Among the 522 participants, 73.4% (n= 383) had phenotype overlap, and mixed T2 and non-T2 inflammation coexisted in 47.5% (n= 248). T2 POS was positively associated with eosinophils, IgE, and fractional exhaled nitric oxide (FeNO), and negatively with Asthma Quality of Life Questionnaire (AQLQ), sputum neutrophils, IL-17A, IL-8, and TNF-α. Non-T2 POS was positively associated with Asthma Control Questionnaire, neutrophils and sputum IL-8, and negatively with AQLQ, forced expiratory volume in 1 s, blood eosinophils, IgE, and FeNO (all P < .05). Patients with phenotypes that are associated with mixed T2 and non-T2 inflammation had elevated T2 inflammation biomarkers but worse asthma control. Both T2 (adjusted β=-0.191, P= .035) and non-T2 (adjusted β= 0.310, P < .001) POS were significantly associated with severe exacerbations. Phenotype overlap is extremely common in asthmatic patients and significantly associated with clinical and inflammatory profiles. Patients with phenotypes associated with mixed T2 and non-T2 inflammation might be unresponsive to medications owing to increased non-T2 inflammation. Multidimensional asthma assessment identifies clinically relevant phenotype overlap.

Evaluation of airway and circulating inflammatory biomarkers for cystic fibrosis drug development

IntroductionBiomarkers of inflammation in blood and sputum can play a critical role in anti-inflammatory drug development in cystic fibrosis (CF). The objectives of this analysis were to examine relationships between airway and systemic measurements of inflammation, associations between inflammatory biomarkers and FEV1, differences in airway and systemic inflammation by baseline covariates, reproducibility of serum biomarkers, and to assess the effects of freezing and delayed processing on sputum analyte measurements. MethodsWe analyzed baseline and serial concentrations of inflammatory markers in blood and induced sputum collected from individuals with CF ages 10 years and older who participated in a multicenter clinical trial. ResultsAmong circulating biomarkers, serum high sensitivity C-reactive protein (hsCRP) and serum amyloid A (SAA) correlated most strongly with each other (rs = 0.85). Comparing sputum-based inflammation measurements, sputum neutrophil elastase and myeloperoxidase (MPO) were the most highly correlated (rs = 0.88). Markers most strongly correlated with ppFEV1 were serum hsCRP (rs = -0.55), SAA (rs =-0.58), and sputum neutrophil elastase (rs = -0.53). Within-subject standard deviation was consistently lower than between-subject standard deviation for all serum biomarkers. Serum calprotectin and MPO had the highest ratio of between-to-within subject variability. Freezing and delayed sputum processing were not associated with significant differences in measurements of sputum neutrophil elastase, IL-1β, or MPO. ConclusionsAmong the biomarkers analyzed, serum hsCRP and sputum neutrophil elastase are promising candidates to include in CF anti-inflammatory clinical trials to avoid redundancy, minimize variation, and serve as correlates of lung disease severity and change.

Relationship between sputum periostin level and inflammatory asthma phenotypes in Egyptian patients

Introduction Asthma is a common chronic inflammatory air way disease which poses a high disease burden worldwide. Asthma is a heterogenous disease with various phenotypes and endotypes. Refractory asthma requires new and personalized approaches to manage it effectively. Periostin is a promising biomarker that may help in predicting severity, prognosis and could be a therapeutic target. We aimed in this study to investigate periostin levels in the sputum of asthmatic Egyptian patients of inflammatory phenotypes and its relation to asthma severity. Subjects and methods This study included 96 adult asthmatic patients; 48 patients with mild-to-moderate bronchial asthma, 48 patients with severe bronchial asthma according to ATS criteria and 10 healthy controls. All participants were subjected to full history taking and clinical examination; pulmonary function tests; skin prick test; induced-sputum analysis for inflammatory cells and periostin. Results Sputum periostin concentrations were significantly higher in patients with asthma than in controls. Sputum periostin is strongly correlated with age and sputum TLC and inversely correlated with FEV1. It is correlated with sputum neutrophil count and sputum eosinophil percentage. Best cut off value for sputum periostin is >528.25 ng/ml to differentiate between mild-to-moderate and severe asthma. Conclusion Sputum periostin levels provide a satisfying diagnostic accuracy in severe asthmatic with persistent airflow limitation than mild-to-moderate asthmatic adults. There is a modest positive correlation between sputum periostin and sputum eosinophilia

The Role of Airways 17β-Estradiol as a Biomarker of Severity in Postmenopausal Asthma: A Pilot Study.

Background: Asthma severity differs according to gender; in adult women, there is higher prevalence and severity of asthma than in men, and it coincides with changes in sex hormones. Recently, a new phonotype of asthma has been identified that appears after menopause, and it may be associated with decreased estrogen levels. Our goal was to study the 17β-estradiol (E2) concentrations in the blood and airways of women affected by asthma onset after menopause, evaluating its possible role in the severity of the disease. Methods: We enrolled 33 consecutive women with a diagnosis of postmenopausal asthma, recruited from the outpatient pulmonary clinic: 18 with severe (SA) and 15 with mild-to-moderate (MMA) asthma. We also included 30 age-matched healthy menopausal women as controls (HS). All subjects enrolled underwent blood and sputum collection (IS), and E2 concentrations were determined in plasma and sputum supernatant samples using an enzyme-linked immunosorbent assay (ELISA) kit. Results: Significantly higher serum concentrations of E2 were found in postmenopausal SA compared to MMA and HS, respectively (33 ± 5.5 vs. 24 ± 6.63 vs. 7.79 ± 1.54 pg/mL, p < 0.05). Similar results were found in the IS: significantly higher levels of E2 were detected in patients with postmenopausal SA compared with MMA and HS, respectively (0.34 ± 0.17 vs. 0.26 ± 0.13 vs. 0.07 ± 0.06 pg/mL, p < 0.05). We found positive correlations between IS E2 concentrations and sputum neutrophil levels in SA group (ρ = 0.52, p < 0.05). Conclusions: Our findings showed the possibility to measure E2 in the airways, and it has increased in postmenopausal asthmatic patients, especially in those with SA. Airways E2 levels may serve as a suitable biomarker of postmenopausal SA to help to phenotype SA patients with neutrophil inflammation.

Predictive factors of response to inhaled corticosteroids in newly diagnosed asthma: A real-world observational study

BackgroundAsthma is characterized by chronic airway inflammation, and inhaled corticosteroids (ICSs) have been recommended as first-line treatment. However, response to ICS treatment is various, and the prediction of response to ICSs is still difficult, especially in individuals with newly diagnosed asthma. ObjectiveTo assess the clinical factors and biomarkers associated with response to ICSs in newly diagnosed asthma. MethodsA total of 150 ICS-naive patients with newly diagnosed asthma in the allergy clinic of a single tertiary hospital in Korea from January 2014 to January 2019 were included in this study. All patients initially received moderate-dose ICSs and were treated for more than 1 year. We compared the clinical characteristics and parameters between patients with and without acute exacerbation (AE) during the study period. ResultsIn this study, 99 patients had no AE (stable asthma group), and 51 patients presented with more than 1 AE (unstable asthma group). The mean (SD) blood eosinophil count (635.7 [780.3] × 103/μL vs 373.4 [266.8] × 103/μL, P = .003) and sputum eosinophil count (15.2% [23.9%] vs 8.3% [15.4%], P = .051) were higher and the sputum neutrophil count (42.9% [35.1%] vs 61.3% [35.1%], P = .057) was lower in the stable asthma group than in the unstable asthma group. ConclusionHigh blood and sputum eosinophil counts can predict a good response to ICS treatment in terms of prevention of AE in individuals with newly diagnosed asthma. The sputum neutrophil count may be an effective predictor of response to ICSs, even though additional studies must be conducted.

BPI-ANCA is expressed in the airways of cystic fibrosis patients and correlates to platelet numbers and Pseudomonas aeruginosa colonization.

Autoantibodies to bactericidal/permeability-increasing protein (BPI), BPI-ANCA, are often present in serum of patients with cystic fibrosis (CF), and correlate to airway colonization with Pseudomonas aeruginosa. The aim of the study was to investigate if BPI-ANCA IgA is also present in the airways of CF patients, and if its presence correlates with neutrophil counts, platelets, and P. aeruginosa DNA in sputum. BPI-ANCA IgA was quantified in serum and sputum samples from adult CF patients (n=45) by ELISA. Sputum neutrophil counts, platelets, and platelet-neutrophil complexes were assessed by flow cytometry, and P. aeruginosa DNA was analysed with RT-PCR. Serum BPI-ANCA IgA was present in 44% of the study participants, and this group also had significantly enhanced BPI-ANCA levels in sputum compared to serum negative patients. Sputum levels of BPI-ANCA IgA correlated with P. aeruginosa DNA (r=0.63, p=0.0003) and platelet counts in sputum (r=0.60, p=0.0002). BPI-ANCA is expressed in the airways of CF patients and correlates with P. aeruginosa load and platelet counts, suggesting a link to airway inflammation and mucosal immunity.

Sputum microbiome profiles identify severe asthma phenotypes of relative stability at 12 to 18 months

Asthma is a heterogeneous disease characterized by distinct phenotypes with associated microbial dysbiosis. Our aim was to identify severe asthma phenotypes based on sputum microbiome profiles and assess their stability after 12 to 18 months. Afurther aim was to evaluate clusters' robustness after inclusion of an independent cohort of patients with mild-to-moderate asthma. In this longitudinal multicenter cohort study, sputum samples were collected for microbiome profiling from a subset of the Unbiased Biomarkers in Prediction of Respiratory Disease Outcomes adult patient cohort at baseline and after 12 to 18 months of follow-up. Unsupervised hierarchical clustering was performed by using the Bray-Curtis β-diversity measure of microbial profiles. For internal validation, partitioning around medoids, consensus cluster distribution, bootstrapping, and topological data analysis were applied. Follow-up samples were studied to evaluate within-patient clustering stability in patients with severe asthma. Cluster robustness was evaluated by using an independent cohort of patients with mild-to-moderate asthma. Data were available for 100 subjects with severe asthma (median age 55 years; 42% males). Two microbiome-driven clusters were identified; they were characterized by differences in asthma onset, smoking status, residential locations, percentage of blood and/or sputum neutrophils and macrophages, lung spirometry results, and concurrent asthma medications (all P values< .05). The cluster 2 patients displayed a commensal-deficient bacterial profile that was associated with worse asthma outcomes than those of the cluster 1 patients. Longitudinal clusters revealed high relative stability after 12 to 18 months in those with severe asthma. Further inclusion of an independent cohort of 24 patients with mild-to-moderate asthma was consistent with the clustering assignments. Unbiased microbiome-driven clustering revealed 2 distinct robust phenotypes of severe asthma that exhibited relative overtime stability. This suggests that the sputum microbiome may serve as a biomarker for better characterizing asthma phenotypes.

Predictors of a good response to inhaled corticosteroids in obesity-associated asthma

IntroductionAsthma in obese subjects is poorly understood. According to GINA guidelines, pulmonologists increase ICS in case of poor asthma control but lung volume restriction may also worsen respiratory symptoms in obese asthmatics leading to overtreatment in this subpopulation. MethodsWe conducted a retrospective study on 1217 asthmatics recruited from University Hospital of Liege. 92 patients with a BMI ≥30 came at least two times at the asthma clinic (mean interval: 335 days). In this obese population, we identified predictors of good (decrease in ACQ ≥0.5) versus poor response (rise in ACQ ≥0.5) to ICS step-up therapy. ResultsObese asthmatics had a poorer asthma control and quality of life as compared to non-obese and exhibited reduced FVC, higher levels of blood leucocytes and markers of systemic inflammation. The proportion of asthma inflammatory phenotypes was similar to that observed in a general population of asthmatics. Among uncontrolled obese asthmatics receiving ICS step-up therapy, 53% improved their asthma control while 31% had a worsening of their asthma. Uncontrolled obese asthmatics showing a good response to increase in ICS had higher ACQ, lower CRP levels, higher sputum eosinophil counts and higher FeNO levels at visit 1. Uncontrolled obese asthmatics that worsened after increasing the dose of ICS had lower FVC, lower sputum eosinophil counts and higher sputum neutrophil counts. ConclusionWe observed poorer asthma control in obese asthmatics despite similar bronchial inflammation. Managing obese asthmatics according to ACQ alone seems to underestimate asthma control and the contribution of restriction to dyspnea. Increasing the dose of ICS in the absence of sputum eosinophilic inflammation or in the presence of restriction or bronchial neutrophilia led to poorer asthma control. In those patients, management of obesity should be the first choice.

Different expression levels of interleukin-35 in asthma phenotypes

BackgroundInterleukin (IL)-35 is a newly discovered inhibitory cytokine which is produced by regulatory B and T lymphocytes and belongs to the IL-12 family. It plays a suppressive role in human inflammatory diseases; however, its role in asthma phenotypes is unclear. Our study focuses on the sputum IL-35 level in patients and investigates different airway inflammation capacities of sputum IL-35 in patients with different asthma phenotypes.ObjectiveWe aimed to determine the sputum IL-35 levels in asthmatic patients with clinical remission phenotypes and control subjects and to investigate possible correlations among lung function, age, sex, fractional exhaled nitric oxide (FeNO), and smoking history in these phenotypes.MethodsSputum samples were collected from patients with clinical asthma remission (n = 89, 37 males, age 52.24 ± 13.32 years) and a healthy control group (n = 19, 9 males, age 44.58 ± 16.3 years). All subjects underwent sputum induction. Induced sputum was assessed for inflammatory cell count, and sputum levels of IL-35 and other cytokines were measured by ELISA and Cytometric Bead Array, respectively.ResultsSputum IL-35 (median (q1, q3)) levels showed no significant difference between asthma patients (4.89 ng/mL (2.97, 22.75)) and healthy controls (6.01 ng/mL (4.09, 30.47)). However, the sputum IL-35 level was significantly reduced in patients with eosinophilic asthma (EA) (3.95 ng/mL (2.80, 11.00)) compared to patients with neutrophilic asthma (NA) (40.59 ng/mL (20.59, 65.06), p = 0.002), paucigranulocytic asthma (PA) (6.25 ng/mL (3.10, 24.60), p = 0.012), and mixed granulocytic asthma (MA) (22.54 ng/mL (2.58, 52.45), p = 0.026). IL-35 levels in sputum showed a positive correlation with sputum neutrophil cells and a negative correlation with FeNO, FEV1% predicted, and FVC predicted. Furthermore, sputum IL-35 had a significant positive association with Th1-related factors and a negative correlation with Th2-related factors.ConclusionsSputum IL-35 is likely involved in different pathophysiological mechanisms of NA and EA and exerts different effects in asthma phenotypes.

Evaluating Risk Factors in Patients with Severe Asthma: A Cross-Sectional Study

Severe asthma (SA) is a major health problem which can be controlled with highdoses of inhaled or systemic glucocorticoids. In this cross-sectional study, 96 patients with SA attending a pulmonary clinic in Rasht, Iran were included. They were identified based on the American Thoracic Society and European Respiratory Society guidelines. Data were collected from spirometry results, asthma control test (ACT), and depression anxiety stressscales. Among these 96 patients with SA, 69 were women (71.9%) and 27 (28.1%) were men. Mean age of patients was 54.5 ± 12.4 years. There was a significant relationship between gender and ACT score (P= 0.03). However, there was no significant relationship between depression severity and ACT score (P> 0.00). This study showed a significant relationshipbetween anxiety and ACT score (P= 0.008). In addition, a significant relationship was seen between frequency of asthma exacerbation, stress, forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (P< 0.05). Thus there are many risk factors in our patients with SA including psychological disorders such as anxiety and depression which cause asthma exacerbations. The study also showed that increased sputum neutrophils are associated with asthma exacerbations.