Identification of Siglec-1-negative alveolar macrophages with proinflammatory phenotypes in chronic obstructive pulmonary disease.

Alveolar macrophages (AMs) in patients with chronic obstructive pulmonary disease (COPD) orchestrate persistent inflammation in the airway. However, subpopulations of AMs participating in chronic inflammation have been poorly characterized. We previously reported that Siglec-1 expression on AMs, which is important for bacteria engulfment, was decreased in COPD. Here, we show that Siglec-1-negative AMs isolated from COPD lung tissues exhibit a proinflammatory phenotype and are associated with poor clinical outcomes in patients with COPD. Using flow cytometry, we segregated three subsets of AMs based on the expression of Siglec-1 and their side scattergram (SSC) and forward scattergram (FSC) properties: Siglec-1+SSChiFSChi, Siglec-1-SSChiFSChi, and Siglec-1-SSCloFSClo subsets. The Siglec-1-SSCloFSClo subset number was increased in COPD. RNA sequencing revealed upregulation of multiple proinflammatory signaling pathways and emphysema-associated matrix metalloproteases in the Siglec-1-SSCloFSClo subset. Gene set enrichment analysis indicated that the Siglec-1-SSCloFSClo subset adopted intermediate phenotypes between monocytes and mature alveolar macrophages. Functionally, these cells produced TNF-α, IL-6, and IL-8 at baseline, and these cytokines were significantly increased in response to viral RNA. The increase in Siglec-1-negative AMs in induced sputum is associated with future exacerbation risk and lung function decline in patients with COPD. Collectively, the novel Siglec-1-SSCloFSClo subset of AMs displays proinflammatory properties, and their emergence in COPD airways may be associated with poor clinical outcomes.NEW & NOTEWORTHY Alveolar macrophages (AMs) in patients with chronic obstructive pulmonary disease (COPD) orchestrate persistent inflammation in the airway. We find that Siglec-1-negative alveolar macrophages have a wide range of proinflammatory landscapes and a protease-expressing phenotype. Moreover, this subset is associated with the pathogenesis of COPD and responds to viral stimuli.

Benefits of budesonide/glycopyrronium/formoterol fumarate dihydrate on lung function and exacerbations of COPD: a post-hoc analysis of the KRONOS study by blood eosinophil level and exacerbation history.

BACKGROUND: Japanese guidelines recommend triple inhaled corticosteroid (ICS)/long-acting muscarinic antagonist (LAMA)/long-acting ß2-agonist (LABA) therapy in patients with chronic obstructive pulmonary disease (COPD) and no concurrent asthma diagnosis who experience frequent exacerbations and have blood eosinophil (EOS) count ≥ 300 cells/mm3, and in patients with COPD and asthma with continuing/worsening symptoms despite receiving dual ICS/LABA therapy. These post-hoc analyses of the KRONOS study in patients with COPD and without an asthma diagnosis, examine the effects of fixed-dose triple therapy with budesonide/glycopyrronium/formoterol fumarate dihydrate (BGF) versus dual therapies on lung function and exacerbations based on blood EOS count - focusing on blood EOS count 100 to < 300 cells/mm3 - as a function of exacerbation history and COPD severity. METHODS: In KRONOS, patients were randomized to receive treatments that included BGF 320/14.4/10 µg, glycopyrronium/formoterol fumarate dihydrate (GFF) 14.4/10 µg, or budesonide/formoterol fumarate dihydrate (BFF) 320/10 µg via metered dose inhaler (two inhalations twice-daily for 24 weeks). These post-hoc analyses assessed changes from baseline in morning pre-dose trough forced expiratory volume in 1 s (FEV1) over 12-24 weeks and moderate or severe COPD exacerbations rates over 24 weeks. The KRONOS study was not prospectively powered for these subgroup analyses. RESULTS: Among patients with blood EOS count 100 to < 300 cells/mm3, least squares mean treatment differences for lung function improvement favored BGF over BFF in patients without an exacerbation history in the past year and in patients with moderate and severe COPD, with observed differences ranging from 62 ml to 73 ml across populations. In this same blood EOS population, moderate or severe exacerbation rates were reduced for BGF relative to GFF by 56% in patients without an exacerbation history in the past year, by 47% in patients with moderate COPD, and by 50% in patients with severe COPD. CONCLUSIONS: These post-hoc analyses of patients with moderate-to-very severe COPD from the KRONOS study seem to indicate clinicians may want to consider a step-up to triple therapy in patients with persistent/worsening symptoms with blood EOS count > 100 cells/mm3, even if disease severity is moderate and there is no recent history of exacerbations. TRIAL REGISTRATION: ClinicalTrials.gov registry number NCT02497001 (registration date, 13 July 2015).

CYP27A1-27-hydroxycholesterol axis in the respiratory system contributes to house dust mite-induced allergic airway inflammation.

BACKGROUND: 27-Hydroxycholesterol (27-HC) derived from sterol 27-hydroxylase (CYP27A1) has pro-inflammatory biological activity and is associated with oxidative stress and chronic inflammation in COPD. However, the role of regulation of CYP27A1- 27-HC axis in asthma is unclear. This study aimed to elucidate the contribution of the axis to the pathophysiology of asthma. METHODS: House dust mite (HDM) extract was intranasally administered to C57BL/6 mice and the expression of CYP27A1 in the airways was analyzed by immunostaining. The effect of pre-treatment with PBS or CYP27A1 inhibitors on the cell fraction in the bronchoalveolar lavage fluid (BALF) was analyzed in the murine model. In vitro, BEAS-2B cells were treated with HDM and the levels of CYP27A1 expression were examined. Furthermore, the effect of 27-HC on the expressions of E-cadherin and ZO-1 in the cells was analyzed. The amounts of RANTES and eotaxin from the 27-HC-treated cells were analyzed by ELISA. RESULTS: The administration of HDM increased the expression of CYP27A1 in the airways of mice as well as the number of eosinophils in the BALF. CYP27A1 inhibitors ameliorated the HDM-induced increase in the number of eosinophils in the BALF. Treatment with HDM increased the expression of CYP27A1 in BEAS-2B cells. The administration of 27-HC to BEAS-2B cells suppressed the expression of E-cadherin and ZO-1, and augmented the production of RANTES and eotaxin. CONCLUSIONS: The results of this study suggest that aeroallergen could enhance the induction of CYP27A1, leading to allergic airway inflammation and disruption of the airway epithelial tight junction through 27-HC production.

[CURRENT STATUS OF SCHOOL LUNCHES RELATED TO FOOD ALLERGY AND UNMET NEEDS OF TEACHERS IN MIYAGI PREFECTURE].

BACKGROUND: The number of students with food allergies is on the increase, while the problems and burdens of school teachers and staff are not yet clear. Our study was designed to identify the unmet needs of school teachers and staff dealing with food allergy in school lunches. METHODS: A written questionnaire was sent by mail to 600 elementary and junior high schools in Miyagi Prefecture. RESULTS: Responses were received from 169 schools. The prevalence of food allergy was 5.6% and the EpiPen possession rate was 0.36%. The most common problems perceived by teachers and staff were the "increase in the number of students with food allergies" and the "diversification of causative foods". Other problems included "uncertainty of foods to be removed" and "insufficient collaboration among teachers, guardians, and doctors," which could be improved by the medical providers. In the free descriptions, many respondents complained of an excessive workload and the mental burden of never making a mistake or missing anything. CONCLUSION: Our survey revealed that while there is a public demand for safe school lunches, the teachers and staff dealing with this demand are under considerable strain. It is necessary to consider reducing the burden, and a sustainable system needs to be established.

[A SURVEY ON MEDICAL CARE FOR ALLERGIC DISEASES IN MIYAGI].

OBJECTIVE: In Miyagi, the number of allergy specialists per population is higher at Sendai city compared to the other areas (non-Sendai areas). Therefore, the healthcare delivery for allergic diseases are unevenly distributed. In the current study, we investigated differences of medical care for allergic diseases between Sendai city and non-Sendai areas. METHODS: We conducted a web-based questionnaire survey to all of hospitals and clinics in the prefecture. The questionnaire responses were analyzed and compared between the Sendai city and non-Sendai areas. RESULTS: Responses to the questionnaire were obtained from 175 hospitals and clinics, including 72 internal physicians, 34 pediatricians, 17 dermatologists, 15 otorhinolaryngologists, 12 ophthalmologists and 25 others. More clinicians in non-Sendai areas felt the difficulty in treating asthma and chronic urticaria than those in Sendai city. Fewer institutions prescribed biologics for severe allergic diseases in non-Sendai areas than in Sendai city, which might be due to the lack of knowledge on the biologic agents. On the other hand, referring patients with anaphylaxis to specialized hospitals tended to be more difficult in Sendai city compared to in non-Sendai areas. Additionally, the regional medical liaison system is needed to refer patients with severe allergic diseases to advanced medical institutions. CONCLUSION: There are unique problems about allergy care in Miyagi.

COVID-19 in a Hairy Cell Leukemia Patient: A Rare Case Report.

The detailed clinical course of coronavirus disease 2019 (COVID-19) in patients with hairy cell leukemia (HCL) is rarely reported. We report the first case of HCL diagnosed with prolonged pancytopenia after COVID-19 infection in Japan. We describe the case of a 56-year-old man who was diagnosed with COVID-19. Computed tomography revealed ground-glass opacities in the bilateral lung lobes as well as splenomegaly. Remdesivir and dexamethasone were administered for the treatment of COVID-19. Since the pancytopenia persisted, bone marrow examination was performed, and he was diagnosed with HCL. Although pancytopenia can occur with COVID-19 alone, clinicians should be alerted regarding the presence of hematologic malignancies in patients in whom pancytopenia persists after COVID-19 treatment or in those with splenomegaly. Further, the condition of all previously reported patients with COVID-19 associated with HCL was severe enough to require mechanical ventilation. This is the first case in which the disease was not severe. The interleukin-6 (IL-6) level was lower in this case than in previous cases, suggesting that racial differences in IL-6 production may have contributed to COVID-19 severity.

Decreased expression of airway epithelial Axl is associated with eosinophilic inflammation in severe asthma.

BACKGROUND: Airway epithelium-derived cytokines are critical to provoke and perpetuate type 2 inflammation in asthma. Yet it is poorly understood how this epithelial cell-driven inflammatory response is negatively regulated. We previously reported that Axl receptor tyrosine kinase was expressed by basal cells in the airway epithelium and had a role in defining their stem cell identity. However, whether and how Axl regulates airway type 2 inflammation remains unknown. METHODS: We performed immunofluorescence staining to compare Axl expression in airway epithelium between non-asthmatic subjects, mild-moderate asthma and severe asthma. We confirmed this result by interrogating public databases of global gene expression in endobronchial biopsies. We then quantified eosinophil numbers infiltrating into the trachea of wild-type or Axl-knockout mice that were intranasally treated with house dust mite extracts (HDM). Cell-based assays using siRNA targeting Axl were further performed to identify molecules involved in Axl-mediated regulation of inflammation. RESULTS: Histological assessments and transcriptome analyses revealed decreases in protein and mRNA of Axl in airway basal cells of severe asthmatics. This reduction of Axl expression was correlated with infiltration of eosinophils and mast cells in severe asthmatics. Eosinophil infiltration was more evident in the trachea of Axl-knockout mice in response to repetitive HDM administration. siRNA-mediated knockdown of Axl increased mRNA and protein expression of granulocyte macrophage-colony stimulating factor (GM-CSF) in human bronchial epithelial cells. CONCLUSIONS: Axl kinase expressed by basal cells may suppress excessive eosinophilic inflammation via inhibition of GM-CSF in the airway. Axl reduction has clinical implications for the pathogenesis of severe asthma.

Effects of indacaterol on the LPS-evoked changes in fluid secretion rate and pH in swine tracheal membrane.

An acquired dysregulation of airway secretion is likely involved in the pathophysiology of chronic bronchitis and chronic obstructive pulmonary disease (COPD). Nowadays, it is widely known that several kinds of long-acting bronchodilators reduce the frequency of COPD exacerbations. However, limited data are available concerning the complementary additive effects on airflow obstruction. Using an optical method and a selective pH indicator, we succeeded in evaluating the gland secretion rate and the pH in swine tracheal membrane. A physiologically relevant concentration of acetylcholine (ACh) 100 nM induced a gradual increase in the amount of gland secretion. Lipopolysaccharides (LPS) accelerated the ACh-induced secretory responses up to around threefold and lowered the pH level significantly. Long-acting ß2-agonists (LABAs) including indacaterol (IND), formoterol, and salmeterol restored the LPS-induced changes in both the hypersecretion and acidification. The subsequent addition of the long-acting muscarine antagonist, glycopyrronium, further increased the pH values. Two different inhibitors for cystic fibrosis transmembrane conductance regulator (CFTR), NPPB and CFTRinh172, abolished the IND-mediated pH normalization in the presence of both ACh and ACh + LPS. Both immunofluorescence staining and western blotting analysis revealed that LPS downregulated the abundant expression of CFTR protein. However, IND did not restore the LPS-induced decrease in CFTR expression on Calu-3 cells. These findings suggest that the activation of cAMP-dependent HCO3- secretion through CFTR would be partly involved in the IND-mediated pH normalization in gland secretion and may be suitable for the maintenance of airway defense against exacerbating factors including LPS.

Efficacy of budesonide/glycopyrronium/formoterol metered dose inhaler in patients with COPD: post-hoc analysis from the KRONOS study excluding patients with airway reversibility and high eosinophil counts.

BACKGROUND: In the Phase III KRONOS study, triple therapy with budesonide/glycopyrronium/formoterol fumarate metered dose inhaler (BGF MDI) was shown to reduce exacerbations and improve lung function versus glycopyrronium/formoterol fumarate dihydrate (GFF) MDI in patients with moderate-to-very severe chronic obstructive pulmonary disease (COPD). However, whether the benefits related to the ICS component of BGF are driven by patients with high blood eosinophil counts (EOS) and/or airway reversibility has not been previously studied. METHODS: KRONOS was a Phase III, double-blind, parallel-group, multicenter, randomized, controlled study of patients with moderate-to-very-severe COPD. Patients were randomized 2:2:1:1 to receive BGF 320/14.4/10 µg, GFF 14.4/10 µg, budesonide/formoterol fumarate dihydrate (BFF) MDI 320/10 µg via a single Aerosphere inhaler, or open-label budesonide/formoterol fumarate dihydrate dry powder inhaler 400/12 µg (BUD/FORM DPI; Symbicort Turbuhaler) twice-daily for 24 weeks. Efficacy outcomes included in this post-hoc analysis were change from baseline in morning pre-dose trough FEV1 over weeks 12-24 and the rate of moderate-to-severe and severe COPD exacerbations. Adverse events in the non-reversible subgroup are also reported. RESULTS: Of 1896 patients analyzed, 948 (50%) were non-reversible and had EOS < 300 cells/mm3. In this group, BGF significantly improved morning pre-dose trough FEV1 versus BFF and BUD/FORM (least squares mean treatment difference, 95% confidence interval [CI] 69 mL [39, 99], unadjusted p < 0.0001 and 51 mL [20, 81], unadjusted p = 0.0011, respectively) and was comparable to GFF. BGF also significantly reduced annual moderate-to-severe exacerbation rates versus GFF (rate ratio [95% CI] 0.53 [0.37, 0.76], unadjusted p = 0.0005), with numerical reductions observed versus BFF and BUD/FORM. These results were similar for the overall study population. Safety findings were generally similar between non-reversible patients with EOS < 300 cells/mm3 and the overall population. CONCLUSIONS: In patients with moderate-to-very-severe COPD without airway reversibility and EOS < 300 cells/mm3, BGF significantly improved morning pre-dose trough FEV1 versus BFF and BUD/FORM and significantly reduced the rate of moderate-to-severe exacerbations versus GFF. These findings demonstrate that BGF can provide benefits for a broad range of patients with COPD, and that the overall findings of the KRONOS primary analysis were not driven by patients with reversible airflow obstruction or high eosinophil counts. Trial registration ClinicalTrials.gov, NCT02497001. Registered 14 July 2015, https://clinicaltrials.gov/ct2/show/NCT02497001.

Triple versus LAMA/LABA combination therapy for patients with COPD: a systematic review and meta-analysis.

BACKGROUND: Recently, the addition of inhaled corticosteroid (ICS) to long-acting muscarinic antagonist (LAMA) and long-acting beta-agonist (LABA) combination therapy has been recommended for patients with COPD who have severe symptoms and a history of exacerbations because it reduces the exacerbations. In addition, a reducing effect on mortality has been shown by this treatment. However, the evidence is mainly based on one large randomized controlled trial IMPACT study, and it remains unclear whether the ICS add-on treatment is beneficial or not. Recently, a large new ETHOS trial has been performed to clarify the ICS add-on effects. Therefore, we conducted a systematic review and meta-analysis to evaluate the efficacy and safety including ETHOS trial. METHODS: We searched relevant randomized control trials (RCTs) and analyzed the exacerbations, quality of life (QOL), dyspnea symptom, lung function and adverse events including pneumonia and mortality, as the outcomes of interest. RESULTS: We identified a total of 6 RCTs in ICS add-on protocol (N = 13,579). ICS/LAMA/LABA treatment (triple therapy) significantly decreased the incidence of exacerbations (rate ratio 0.73, 95% CI 0.64-0.83) and improved the QOL score and trough FEV1 compared to LAMA/LABA. In addition, triple therapy significantly improved the dyspnea score (mean difference 0.33, 95% CI 0.18-0.48) and mortality (odds ratio 0.66, 95% CI 0.50-0.87). However, triple therapy showed a significantly higher incidence of pneumonia (odds ratio 1.52, 95% CI 1.16-2.00). In the ICS-withdrawal protocol including 2 RCTs, triple therapy also showed a significantly better QOL score and higher trough FEV1 than LAMA/LABA. Concerning the trough FEV1, QOL score and dyspnea score in both protocols, the differences were less than the minimal clinically important difference. CONCLUSION: Triple therapy causes a higher incidence of pneumonia but is a more preferable treatment than LAMA/LABA due to the lower incidence of exacerbations, higher trough FEV1 and better QOL score. In addition, triple therapy is also superior to LABA/LAMA due to the lower mortality and better dyspnea score. However, these results should be only applied to patients with symptomatic moderate to severe COPD and a history of exacerbations. CLINICAL TRIAL REGISTRATION: PROSPERO; CRD42020191978.

Upregulation of leukocyte immunoglobulin-like receptor B4 on interstitial macrophages in COPD; their possible protective role against emphysema formation.

BACKGROUND: Leukocyte immunoglobulin-like receptor B4 (LILRB4) is one of the inhibitory receptors in various types of immune cells including macrophages. Previous reports suggested that LILRB4 could be involved in a negative feedback system to prevent excessive inflammatory responses. However, its role has been unclear in chronic obstructive pulmonary disease (COPD), in which macrophages play a crucial role in the pathogenesis. In this study, we aimed to examine the changes of LILRB4 on macrophages both in the lung specimens of COPD patients and the lungs of a mouse emphysema model. We then tried to compare the differences in both inflammation and emphysematous changes of the model between wild-type and LILRB4-deficient mice in order to elucidate the role of LILRB4 in the pathogenesis of COPD. METHODS: We prepared single-cell suspensions of resected lung specimens of never-smokers (n = 21), non-COPD smokers (n = 16), and COPD patients (n = 14). The identification of LILRB4-expressing cells and the level of LILRB4 expression were evaluated by flow cytometry. We analyzed the relationships between the LILRB4 expression and clinical characteristics including respiratory function. In the experiments using an elastase-induced mouse model of emphysema, we also analyzed the LILRB4 expression on lung macrophages. We compared inflammatory cell accumulation and emphysematous changes induced by elastase instillation between wild-type and LILRB4-deficient mice. RESULTS: The levels of surface expression of LILRB4 are relatively high on monocyte linage cells including macrophages in the human lungs. The percentage of LILRB4+ cells in lung interstitial macrophages was increased in COPD patients compared to non-COPD smokers (p = 0.018) and correlated with the severity of emphysematous lesions detected by CT scan (rs = 0.559, p < 0.001), whereas the amount of smoking showed no correlation with LILRB4 expression. Increased LILRB4 on interstitial macrophages was also observed in elastase-treated mice (p = 0.008). LILRB4-deficient mice showed severer emphysematous lesions with increased MMP-12 expression in the model. CONCLUSIONS: LILRB4 on interstitial macrophages was upregulated both in human COPD lungs and in a mouse model of emphysema. This upregulated LILRB4 may have a protective effect against emphysema formation, possibly through decreasing MMP-12 expression in the lungs.

PGC-1α regulates airway epithelial barrier dysfunction induced by house dust mite.

BACKGROUND: The airway epithelial barrier function is disrupted in the airways of asthmatic patients. Abnormal mitochondrial biogenesis is reportedly involved in the pathogenesis of asthma. However, the role of mitochondrial biogenesis in the airway barrier dysfunction has not been elucidated yet. This study aimed to clarify whether the peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α), a central regulator of mitochondrial biogenesis, is involved in the disruption of the airway barrier function induced by aeroallergens. METHODS: BEAS-2B cells were exposed to house dust mite (HDM) and the expressions of PGC-1α and E-cadherin, a junctional protein, were examined by immunoblotting. The effect of SRT1720, a PGC-1α activator, was investigated by immunoblotting, immunocytochemistry, and measuring the transepithelial electrical resistance (TEER) on the HDM-induced reduction in mitochondrial biogenesis markers and junctional proteins in airway bronchial epithelial cells. Furthermore,the effects of protease activated receptor 2 (PAR2) inhibitor, GB83, Toll-like receptor 4 (TLR4) inhibitor, lipopolysaccharide from Rhodobacter sphaeroides (LPS-RS), protease inhibitors including E64 and 4-(2-Aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF) on the HDM-induced barrier dysfunction were investigated. RESULTS: The amounts of PGC-1α and E-cadherin in the HDM-treated cells were significantly decreased compared to the vehicle-treated cells. SRT1720 restored the expressions of PGC-1α and E-cadherin reduced by HDM in BEAS-2B cells. Treatment with SRT1720 also significantly ameliorated the HDM-induced reduction in TEER. In addition, GB83, LPS-RS, E64 and AEBSF prevented the HDM-induced reduction in the expression of PGC1α and E-cadherin. CONCLUSIONS: The current study demonstrated that HDM disrupted the airway barrier function through the PAR2/TLR4/PGC-1α-dependent pathway. The modulation of this pathway could be a new approach for the treatment of asthma.

Decreased expression of a phagocytic receptor Siglec-1 on alveolar macrophages in chronic obstructive pulmonary disease.

BACKGROUND: Alveolar macrophages are professional phagocytes that remove microbial pathogens inhaled into the lung. The phagocytic ability is compromised in chronic obstructive pulmonary disease (COPD). However, the molecular mechanisms underlying this defect in phagocytosis are not clearly defined. MATERIALS AND METHODS: Cell suspensions were collected from lung tissues of patients undergoing lung resection. Alveolar macrophages were detected as FSChi/ SSChi/CD45+/CD206+ cells in the isolated cell suspension by flow-cytometry. The cell surface expression of plasma membrane-bound phagocytic receptors (Fcγ receptor I (FcγRI), a complement receptor CD11b, macrophage scavenger receptor-1 (MSR-1), CD36 and Siglec-1) was determined on the alveolar macrophages. Correlations between the expression levels of the phagocytic receptors and disease severity were analysed. Phagocytosis of fluorescence-tagged bacteria by human alveolar macrophages was evaluated. RESULTS: The flow-cytometry analyses revealed that FcγRI, CD11b, MSR-1 and Siglec-1, but not CD36, were expressed on human alveolar macrophages. Among these receptors, Siglec-1 expression was significantly decreased on alveolar macrophages in COPD ex-smokers (n = 11), compared to control never-smokers (n = 11) or control ex-smokers (n = 9). The Siglec-1 expression on alveolar macrophages was significantly correlated with lung function (forced expiratory volume in 1 s) and with the severity of emphysema. Treatment of human alveolar macrophages with an anti-Siglec1 blocking antibody decreased phagocytosis of non-typeable Haemophilus influenzae (NTHi). CONCLUSION: Our findings demonstrated reduced expression of Siglec-1 on alveolar macrophages in COPD, which is involved in engulfment of NTHi.

Treatment with LABA versus LAMA for stable COPD: a systematic review and meta-analysis.

BACKGROUND: Inhaled bronchodilators including long-acting beta-agonist (LABA) and long-acting muscarinic antagonist (LAMA) play a central role in the treatment of stable chronic obstructive pulmonary disease (COPD). However, it is still unclear whether LABA or LAMA should be used for the initial treatment. Therefore, we conducted a systematic review and meta-analysis to evaluate the efficacy and safety of LABA versus LAMA in patients with stable COPD. METHODS: We searched relevant randomized control trials (RCTs) with a period of treatment of at least 12 weeks and analyzed the exacerbations, quality of life, dyspnea score, lung function and adverse events as the outcomes of interest. RESULTS: We carefully excluded unblinded data and identified a total of 19 RCTs (N = 28,211). LAMA significantly decreased the exacerbations compared to LABA (OR 0.85, 95% CI 0.74 to 0.98; P = 0.02). In St George's Respiratory Questionnaire and transitional dyspnoea index score, there were no differences between LABA and LAMA treatment. Compared to LABA, there was a small but significant increase in the trough FEV1 after LAMA treatment (Mean difference 0.02, 95% CI 0.01 to 0.03, P = 0.0006). In the safety components, there was no difference in the serious adverse events between LABA and LAMA. However, LAMA showed a significantly lower incidence of total adverse events compared to LABA (OR 0.92, 95% CI 0.86 to 0.98; P = 0.02). CONCLUSION: Treatment with LAMA in stable COPD provided a significantly lower incidence of exacerbation and non-serious adverse events, and a higher trough FEV1 compared to LABA. TRIAL REGISTRATION: (PROSPERO: CRD42019144764).

Nitrosative stress in patients with asthma-chronic obstructive pulmonary disease overlap.

BACKGROUND: Asthma-chronic obstructive pulmonary disease overlap (ACO) has frequent exacerbations and a poor quality of life and prognosis compared with those of chronic obstructive pulmonary disease alone. However, the pathogenesis of ACO has not been fully elucidated yet. OBJECTIVES: The aim of this study was to investigate nitrosative stress, which causes a redox imbalance and tissue inflammation in the airways of patients with ACO, and to evaluate the relationship between nitrosative stress and the clinical course in study subjects. METHODS: Thirty healthy subjects and 56 asthmatic patients participated in this study. The asthmatic patients were divided into 33 asthmatic patients and 23 patients with ACO. The study subjects had been followed prospectively for 2 years to evaluate the clinical course. Nitrosative stress was evaluated based on the production of 3-nitrotyrosine (3-NT) in sputum cells. RESULTS: Production of 3-NT was significantly enhanced in patients with ACO compared with that in asthmatic patients. Amounts of reactive persulfides and polysulfides, newly identified powerful antioxidants, were significantly decreased in the ACO group. Baseline levels of 3-NT were significantly correlated with the frequency of exacerbations and decrease in FEV1 adjusted by age, smoking history, and blood eosinophil count. The 3-NT-positive cells were also significantly correlated with amounts of proinflammatory chemokines and cytokines. CONCLUSIONS: These findings suggested that greater nitrosative stress occurred in the airways of patients with ACO, and the degree of nitrosative stress was correlated with an impairment in the clinical course. Nitrosative stress might be related to the pathogenesis of ACO.

[A CASE OF BRONCHIAL ASTHMA IN A YOUNGER PATIENT WITH VOCAL CORD DYSFUNCTION].

We present a case of a 17-year-old woman with a history of bronchial asthma since two years of age. She had daily asthma attacks from the age of fourteen, and the addition of oral corticosteroids and omalizumab to regular inhaled corticosteroid inhalation failed to relieve symptoms. She was referred to our hospital for detailed examination. On admission, physical examination was normal, but she had complained of dyspnea at the round. Monophonic wheezes and stridor were heard over the anterior neck, while no rales were audible over any part of the chest. Laryngoscopy revealed paradoxical movement of the vocal cords, and a diagnosis of vocal cord dysfunction (VCD) was made. The apparent severe asthma symptoms were considered to reflect VCD, and the treatment for bronchial asthma was stepped down without any recurrence of asthma attacks. Although the etiology of the VCD was unknown, VCD is more common in young women, so stress and personality factors are thought to be involved. It has been noted that childhood asthma often improves between childhood and adolescence, but refractory cases have been noted. In intractable bronchial asthma cases, it is necessary to consider the complications of other diseases, such as VCD, and to perform appropriate management.

Axl kinase drives immune checkpoint and chemokine signalling pathways in lung adenocarcinomas.

Axl receptor tyrosine kinase is involved in the growth and metastasis and is an indicator of poor prognosis in several cancers including lung cancers. Although a mitogen-activated protein kinase (MAPK) pathway and an epithelial-to-mesenchymal transition (EMT) program are critical, molecular mechanisms underlying the Axl-driven cancer progression have not been fully elucidated. We aimed to identify molecules up-regulated by Axl kinase in lung adenocarcinomas. Through the global gene expression analysis and the functional annotation clustering, we found that AXL expression positively correlated with mRNA expressions of immune checkpoint molecules and chemokine receptors in non-small-cell lung cancers. Validation cohorts including our biobank confirmed that the AXL expression significantly correlated with expression of genes encoding programmed death-ligand1 (PD-L1) and CXC chemokine receptor 6 (CXCR6) in lung adenocarcinoma, especially in epidermal growth factor receptor (EGFR) mutation-positive adenocarcinoma. Pharmacological inhibition of Axl kinase activity decreased mRNA expressions of PD-L1 and CXCR6 in EGFR mutation-positive cell lines. Our data indicates the novel role of Axl kinase as a driver of immune checkpoint molecules and chemokine signalling pathways in the progression of lung adenocarcinomas. This study also highlights the necessity of clinical trials in order to test the efficacy of Axl kinase inhibition in the Axl-highly expressing subset of lung adenocarcinomas. .

Increase in circulating ACE-positive endothelial microparticles during acute lung injury.

Circulating endothelial microparticles (EMPs) are considered to be markers of endothelial injury, and lung microvascular endothelial cells express higher levels of angiotensin-converting enzyme (ACE). The aim of this study is to examine whether the number of ACE+ microvascular EMPs could be a prognostic marker for the development of acute respiratory distress syndrome (ARDS) in septic patients.The numbers of EMPs and ACE+ EMPs in the culture supernatant from human microvascular endothelial cells, as well as in the blood of mouse lung injury models and septic patients (n=82), were examined using flow cytometry.ACE+ EMPs in the culture supernatant from pulmonary microvascular endothelial cells increased after exposure to an inflammatory stimulus. In the mouse lung injury models, the circulating ACE+ EMPs and ACE+ EMP/EMP ratio were higher than in the controls (p<0.001). The ACE+ EMP/EMP ratio was correlated with the wet/dry lung ratio (rs=0.775, p<0.001). The circulating ACE+ EMPs and ACE+ EMP/EMP ratio on admission were significantly increased in septic patients who developed ARDS compared with septic patients who did not (p<0.001).Therefore, circulating ACE+ EMPs may be a prognostic marker for the development of ARDS in the septic patients.

Oxidative stress enhances the expression of IL-33 in human airway epithelial cells.

BACKGROUND: Interleukin-33 (IL-33) is a cytokine belonging to the IL-1 family, and its possible involvement in the pathophysiology of COPD and viral-induced exacerbations has been demonstrated. IL-33 has been shown to be increased in the airway epithelial cells from COPD patients, but the regulating mechanism of IL-33 expression in airway epithelial cells remains largely unknown. In the current study, we examined whether oxidative stress, which participates in the pathogenesis of COPD, affects the expression of IL-33 in airway epithelial cells and also evaluated the effect during viral infection. METHODS: The involvement of oxidative stress in the expression of IL-33, and its signal pathway was examined after stimulation with hydrogen peroxide (H2O2), with or without stimulation by polyinosinic-polycytidylic acid [poly (I:C)], a synthetic analogue of dsRNA that mimics viral infection, or rhinovirus infection in NCI-H292 cells and primary human bronchial epithelial cells (HBECs). In addition, the effect of antioxidant, N-acetylcysteine (NAC) in the expression of IL-33 was compared between HBECs from healthy subjects and those from COPD patients. RESULTS: Treatment with H2O2 significantly potentiated IL-33 expression in NCI-H292 cells, and the potentiation was reversed by NAC treatment. Mitogen-activated protein kinase (MAPK) inhibitors, but not nuclear factor-kappa B inhibitors, also significantly decreased the H2O2-potentiated IL-33 expression. In addition, H2O2 significantly potentiated the poly (I:C)- or rhinovirus-stimulated IL-33 expression. In HBECs from healthy subjects, H2O2-potentiated IL-33 expression and its reversal by NAC was also confirmed. Under the condition without H2O2-stimulation, treatment with NAC significantly decreased the expression of IL-33 in HBECs from COPD patients, but not in those from healthy subjects. CONCLUSIONS: These results demonstrate that oxidative stress involves in the expression of IL-33 in airway epithelial cells via MAPK signal pathway and it augments IL-33 expression during viral infection. This mechanism may participate in the regulation of IL-33 expression in airway epithelial cells in COPD and the viral-induced exacerbations. Modulation of this pathway could become a therapeutic target for viral-induced exacerbations of COPD.