Increased Muc5AC and Decreased Ciliated Cells in Severe Asthma Partially Restored by Inhibition of IL-4Rα Receptor.

BACKGROUND: The role of IL-13 on the airway epithelium in severe asthma leading to airway remodeling remains poorly understood. OBJECTIVE: To study IL-13 induced airway remodeling on goblet cells and cilia in the airway epithelium in severe asthma and the impact of an anti-IL4Rα antibody, dupilumab, in vitro. METHODS: Quantitative CT (qCT) lungs and endobronchial biopsies and brushings were obtained in 51 participants (22 severe, 11 non-severe asthma and 18 healthy participants) in the Severe Asthma Research Program (SARPIII) and measured for mucin and cilia related proteins. Epithelial cells were differentiated in air-liquid interphase (ALI) with IL-13 +/-dupilumab and assessed for mucin, cilia, cilia beat frequency (CBF) and epithelial integrity (transepithelial electrical resistance, TEER). RESULTS: Increased Muc5AC (Δ+263.2±92.7 lums/EpiArea) and decreased ciliated cells (Δ-0.07±0.03 Foxj1+cells/EpiArea) were observed in biopsies from severe asthma when compared to healthy (p<0.01 and p=0.047 respectively). RNAseq of epithelial cell brushes confirmed a Muc5AC increase with a decrease in a 5-gene cilia-related mean in severe asthma compared to healthy (all p<0.05). IL-13 (5 ng/mL) differentiated ALI cultures of healthy and asthmatic (severe and non-severe participants) increased Muc5AC, decreased cilia (α-acytl-tubulin) in healthy (Δ+6.5±1.5%, Δ-14.1±2.7%; all p<0.001 respectively) and asthma (Δ+4.4±2.5%, Δ-13.1±2.7%; p=0.084, p<0.001 respectively); decreased epithelial integrity (TEER) in healthy (-140.9±21.3 [ohms], p<0.001) while decreasing CBF in asthma (Δ-4.4±1.7 [Hz], p<0.01). When dupilumab was added to ALI with IL-13, there was no significant decrease in Mu5AC but there was restoration of cilia in healthy and asthma participants (absolute increase of 67.5% and 32.5% cilia, all p<0.05 respectively) while CBF increased (Δ+3.6±1.1 [Hz], p<0.001) and TEER decreased (only in asthma Δ-37.8±16.2 [ohms] p<0.05). CONCLUSIONS: IL-13 drives features of airway remodeling in severe asthma which are partially reversed by inhibiting IL-4Rα receptor in vitro.

Discovery and Validation of a Volatile Signature of Eosinophilic Airway Inflammation in Asthma.

RATIONALE: Volatile organic compounds (VOCs) in asthmatic breath may be associated with sputum eosinophilia. We developed a volatile biomarker-signature to predict sputum eosinophilia in asthma. METHODS: VOCs emitted into the space above sputum samples (headspace) from severe asthmatics (n=36) were collected onto sorbent tubes and analysed using thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). Elastic net regression identified stable VOCs associated with sputum eosinophilia ≥3% and generated a volatile biomarker signature. This VOC signature was validated in breath samples from: (I) acute asthmatics according to blood eosinophilia ≥0.3x109cells/L or sputum eosinophilia of ≥ 3% in the UK EMBER consortium (n=65) and U-BIOPRED-IMI consortium (n=42). Breath samples were collected onto sorbent tubes (EMBER) or Tedlar bags (U-BIOPRED) and analysed by gas-chromatography-mass spectrometry (GC×GC-MS -EMBER or GC-MS -U-BIOPRED). MAIN RESULTS: The in vitro headspace identified 19 VOCs associated with sputum eosinophilia and the derived VOC signature yielded good diagnostic accuracy for sputum eosinophilia ≥ 3% in headspace (AUROC (95% CI) 0.90(0.80-0.99), p<0.0001), correlated inversely with sputum eosinophil % (rs= -0.71, p<0.0001) and outperformed FeNO (AUROC (95% CI) 0.61(0.35-0.86). Analysis of exhaled breath in replication cohorts yielded a VOC signature AUROC (95% CI) for acute asthma exacerbations of 0.89(0.76-1.0) (EMBER cohort) with sputum eosinophilia and 0.90(0.75-1.0) in U-BIOPRED - again outperforming FeNO in U-BIOPRED 0.62 (0.33-0.90). CONCLUSIONS: We have discovered and provided early-stage clinical validation of a volatile biomarker signature associated with eosinophilic airway inflammation. Further work is needed to translate our discovery using point of care clinical sensors.

Downregulation of otulin induces inflammasome activation in neutrophilic asthma.

BACKGROUND: Neutrophilic asthma (NA) is a severe asthma phenotype associated with steroid resistance and IL-1ß overproduction; however, the exact mechanism remains unclear. Moreover, the dysfunction of TNF-α signaling pathway, a regulator of IL-1ß production, was associated with the deficiency of ovarian tumor protease deubiquitinase with linear linkage specificity (otulin) in autoimmune patients. OBJECTIVE: We hypothesized that otulin downregulation in macrophages (Mφ) could trigger Mφ activation via the nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome signaling pathway. METHODS: We assessed the expressions of otulin in blood monocyte subsets from NA patients and in alveolar Mφ from NA mice. Additionally, we evaluated the functional consequences of otulin deficiency in bone marrow-derived Mφ. The effects of inhibiting receptor-interacting protein kinase (RIPK)-1 and RIPK-3 on neutrophils and group 3 innate lymphoid cells (ILC3s) were assessed in vitro and in vivo. RESULTS: When comparing nonclassical monocytes, a significant downregulation of otulin in the intracellular components was observed in NA patients compared to healthy controls (P = .005). Moreover, isolated alveolar Mφ from the NA mice exhibited lower otulin expression compared to those from control mice. After otulin knockdown in bone marrow-derived Mφ, we observed spontaneous IL-1ß production depending on NLRP3 inflammasome. Moreover, the infiltrated neutrophils and ILC3s were significantly decreased by combined treatment of RIPK-1 and RIPK-3 inhibitors through blocking IL-1ß release in NA. CONCLUSIONS: IL-1ß overproduction caused by a deficiency of otulin, an upstream triggering factor, could be a promising diagnostic and therapeutic target for NA.

Anti-IL-4R versus anti-IL-5/5R after anti-IL-5/5R failure in asthma: An emulated target trial.

BACKGROUND: Switching biologics is now common practice in severe eosinophilic asthma. After insufficient response to anti-IL-5 or 5 receptor (anti-IL-5/5R), the optimal switch between an anti-IL-4R mAb (interclass) or another anti-IL-5/5R drug (intraclass) remains unknown. OBJECTIVE: We sought to compare the effectiveness of these 2 strategies in asthma control in patients with severe eosinophilic asthma and insufficient response to an anti-IL-5/5R mAb. METHODS: We emulated a target randomized trial using observational data from the Recherche sur les AsthMes SEvèreS (RAMSES) cohort. Eligible patients were switched to an anti-IL-4R mAb or another anti-IL-5/5R drug after insufficient response to an anti-IL-5/5R mAb. The primary outcome was the change in Asthma Control Test score at 6 months. RESULTS: Among the 2046 patients in the cohort, 151 were included in the study: 103 switched to an anti-IL-4R mAb and 48 to another anti-IL-5/5R. At 6 months, the difference in Asthma Control Test score improvement was not statistically significant (mean difference groups, 0.82 [-0.47 to 2.10], P = .213). The interclass group exhibited greater cumulative reduction in oral corticosteroid dose (Pinter-intra, -1.05 g [-1.76 to -0.34], P = .041). The interclass group had a better effect, although not significantly, on reducing exacerbations (Δinter-intra, -0.37 [-0.77 to 0.02], P = .124) and increasing lung function (FEV1) (126.8 mL [-12.7 to 266.4], P = .124). CONCLUSIONS: After anti-IL-5/5R mAb insufficient response, switching to dupilumab demonstrated similar improvement in Asthma Control Test scores compared with intraclass switching. However, it appeared more effective in reducing oral corticosteroid use. Larger studies are warranted to confirm these results.

A novel syndrome of silent rhinovirus-associated bronchoalveolitis in children with recurrent wheeze.

BACKGROUND: Rhinovirus (RV) infections trigger wheeze episodes in children. Thus, understanding of the lung inflammatory response to RV in children with wheeze is important. OBJECTIVES: This study sought to examine the associations of RV on bronchoalveolar lavage (BAL) granulocyte patterns and biomarkers of inflammation with age in children with treatment-refractory, recurrent wheeze (n = 616). METHODS: Children underwent BAL to examine viral nucleic acid sequences, bacterial cultures, granulocyte counts, and phlebotomy for both general and type-2 inflammatory markers. RESULTS: Despite the absence of cold symptoms, RV was the most common pathogen detected (30%), and when present, was accompanied by BAL granulocytosis in 75% of children. Compared to children with no BAL pathogens (n = 341), those with RV alone (n = 127) had greater (P < .05) isolated neutrophilia (43% vs 16%), mixed eosinophils and neutrophils (26% vs 11%), and less pauci-granulocytic (27% vs 61%) BAL. Children with RV alone furthermore had biomarkers of active infection with higher total blood neutrophils and serum C-reactive protein, but no differences in blood eosinophils or total IgE. With advancing age, the log odds of BAL RV alone were lower, 0.82 (5th-95th percentile CI: 0.76-0.88; P < .001), but higher, 1.58 (5th-95th percentile CI: 1.01-2.51; P = .04), with high-dose daily corticosteroid treatment. CONCLUSIONS: Children with severe recurrent wheeze often (22%) have a silent syndrome of lung RV infection with granulocytic bronchoalveolitis and elevated systemic markers of inflammation. The syndrome is less prevalent by school age and is not informed by markers of type-2 inflammation. The investigators speculate that dysregulated mucosal innate antiviral immunity is a responsible mechanism.

Investigation of lactotransferrin messenger RNA expression levels as an anti-type 2 asthma biomarker.

BACKGROUND: Lactotransferrin (LTF) has an immunomodulatory function, and its expression levels are associated with asthma susceptibility. OBJECTIVES: We sought to investigate LTF messenger RNA (mRNA) expression levels in human bronchial epithelial cells (BECs) as an anti-type 2 (T2) asthma biomarker. METHODS: Association analyses between LTF mRNA expression levels in BECs and asthma-related phenotypes were performed in the Severe Asthma Research Program (SARP) cross-sectional (n = 155) and longitudinal (n = 156) cohorts using a generalized linear model. Correlation analyses of mRNA expression levels between LTF and all other genes were performed by Spearman correlation. RESULTS: Low LTF mRNA expression levels were associated with asthma susceptibility and severity (P < .025), retrospective and prospective asthma exacerbations, and low lung function (P < 8.3 × 10-3). Low LTF mRNA expression levels were associated with high airway T2 inflammation biomarkers (sputum eosinophils and fractional exhaled nitric oxide; P < 8.3 × 10-3) but were not associated with blood eosinophils or total serum IgE. LTF mRNA expression levels were negatively correlated with expression levels of TH2 or asthma-associated genes (POSTN, NOS2, and MUC5AC) and eosinophil-related genes (IL1RL1, CCL26, and IKZF2) and positively correlated with expression levels of TH1 and inflammation genes (IL12A, MUC5B, and CC16) and TH17-driven cytokines or chemokines for neutrophils (CXCL1, CXCL6, and CSF3) (P < 3.5 × 10-6). CONCLUSIONS: Low LTF mRNA expression levels in BECs are associated with asthma susceptibility, severity, and exacerbations through upregulation of airway T2 inflammation. LTF is a potential anti-T2 biomarker, and its expression levels may help determine the balance of eosinophilic and neutrophilic asthma.

Soluble E-Cadherin Contributes to Airway Inflammation in Severe Asthma.

Impaired airway epithelial barrier and decreased expression of E-cadherin are key features of severe asthma. As a gatekeeper of the mucosa, E-cadherin can be cleaved from the cell surface and released into the apical lumen as a soluble form (sE-cadherin).This study was aimed to investigate the role of sE-cadherin in severe asthma.Induced sputum was obtained from healthy subjects and patients with asthma. Two murine models of severe asthma were established using either TDI (toluene diisocyanate) or OVA (ovalbumin)/CFA (complete Freund's adjuvants). The role of sE-cadherin in severe asthma was evaluated by intraperitoneal injection of DECMA-1, a neutralizing antibody against sE-cadherin. Mice or THP-1-derived macrophages were treated with recombinant sE-cadherin to explore the pro-inflammatory mechanism of sE-cadherin.Severe asthma patients had a significantly higher sputum sE-cadherin level than the health subjects with mild to moderate asthma, which were positively correlated with sputum HMGB1 level and glucocorticoid dosage required for daily control. Allergen exposure markedly increased sE-cadherin level in the bronchoalveolar lavage fluid in mice. Treatment of DECMA-1 significantly attenuated allergen-induced airway inflammation and hyperresponsivenes in both models of severe asthma. While exposure to recombinant sE-cadherin dramatically up-regulated VEGF expression in THP-1-derived macrophages, and increased neutophlil and eosinophil infiltration into the airway as well as the release of VEGF and IL-6 in mice, both of which can be suppressed by pharmacological inhibition of ERK signaling.Taken together, our data indicated that sE-cadherin contributed to the airway inflammation of severe asthma in an ERK-depedent pathway.

MiR-155-5p Differentially Regulates IL-13Rα1 and IL-13Rα2 Expression and Signalling, Driving Abnormal Lung Epithelial Cell Phenotype in Severe Asthma.

MiR-155-5p is known to increase in innate and adaptive immune cells in response to IL-13 and is associated with asthma severity. However, little is known about its role in airway structural cells. BECs isolated from healthy donors and severe asthma patients were stimulated with IL-13. MiR-155-5p expression and release were measured by RT-PCR in BECs and in their derived exosomes. Modulation of miR-155-5p in BECs was performed using transfection of miR-155-5p inhibitor and mimic. IL-13Rα1, IL-13Rα2, MUC5AC, IL-8 and Eotaxin-1 expression were measured by RT-PCR and western blot. BECs repair process was assessed by wound healing assay. IL-13Rα1 and IL-13Rα2 expression and downstream pathways were evaluated by western blot. Dual Luciferase assay was used to determine miR-155-5p target genes associated to IL-13 receptors signaling. BECs from severe asthma showed an increased expression and exosomal release of miR-155-5p at baseline that was amplified by IL-13 stimulation. BECs from asthmatics expressed more IL-13Rα1 and less IL-13Rα2 than healthy donors and IL-13Rα1 but not IL-13Rα2 induced miR-155-5p expression under IL-13 stimulation. MiR-155-5p overexpression favored MUC5AC, IL-8 and Eotaxin-1 through IL-13Rα1/SOCS1/STAT6 pathway to the detriment of a delayed repair process with a downregulated IL-13Rα2/MAPK14/c-Jun/c-Fos signaling. Dual Luciferase assay confirmed that miR-155-5p modulates both IL-13 receptors pathways by directly targeting SOCS1, c-Fos and MAPK14. MiR-155-5p is overexpressed in severe asthma BECs and regulates IL-13Rα1 and IL-13Rα2 expression and signaling, favoring expression of mucin and eosinophils related genes to detriment of airway repair. These results show that miR-155-5p may contribute to airway epithelial cell dysfunction in severe asthma.

A new Anticalin protein for IL-23 inhibits non-type 2 allergen-driven mouse lung inflammation and airway hyperresponsiveness.

Severe asthma is a syndromic label assigned to patients based on clinical parameters, yet there are diverse underlying molecular endotypes in severe asthma pathobiology. Immunophenotyping of asthma biospecimens commonly includes a mixture of granulocytes and lymphocytes. Recently, a subset of severe asthma patients was defined as non-type 2 with neutrophil-enriched inflammation associated with increased Th17 CD4+ T cells and IL-17 levels. Here, we used an allergen-driven mouse model of increased IL-17 and mixed granulocyte lung inflammation to determine the impact of upstream regulation by an Anticalin protein that specifically binds IL-23. Airway administration of the IL-23 binding Anticalin protein (AcIL-23) decreased lung neutrophils, eosinophils, macrophages, and lymphocytes, IL-17+ CD4 T cells, mucous cell metaplasia and methacholine-induced airway hyperresponsiveness. Selective targeting of IL-23 with a monoclonal antibody (IL-23p19) (αIL-23) also decreased macrophages, IL-17+ CD4 T cells and airway hyperresponsiveness. In contrast, a monoclonal antibody against IL-17A (αIL-17A) had no significant effect on airway hyperresponsiveness, but did decrease lung neutrophils, macrophages, and IL-17+ CD4 T cells. Targeting the IL-23 pathway did not significantly change IL-5+ or IL-13+ CD4 T cells. Together, these data indicate that airway AcIL-23 mirrored the activity of systemic anti-IL-23 antibody to decrease airway hyperresponsiveness in addition to mixed granulocytic inflammation, and that these protective actions were broader than blocking only IL-17A or IL-5, which selectively decreased airway neutrophils and eosinophils, respectively.

In mouse model of mixed granulocytic asthma with corticosteroid refractoriness, Bronchom mitigates airway hyperresponsiveness, inflammation and airway remodeling.

BACKGROUND: Asthma is a heterogeneous, inflammatory disease with several phenotypes and endotypes. Severe asthmatics often exhibit mixed granulocytosis with reduced corticosteroid sensitivity. Bronchom is a newly developed Ayurvedic prescription medicine, indicated for the treatment of obstructive airway disorders. The purpose of the present study was to evaluate the in-vivo efficacy of Bronchom in mouse model of mixed granulocytic asthma with steroidal recalcitrance. METHODS: High-performance thin layer chromatography (HPTLC) and Ultra-high performance liquid chromatography (UHPLC) were employed to identify and quantitate the phytometabolites present in Bronchom. The preclinical effectiveness of Bronchom was assessed in house dust mite (HDM) and Complete Freund's adjuvant (CFA)-induced mixed granulocytic asthma model in mice. High dose of dexamethasone was tested parallelly. Specific-pathogen-free C57BL/6 mice were immunized with HDM and CFA and nineteen days later, they were intranasally challenged with HDM for four consecutive days. Then the mice were challenged with nebulized methacholine to evaluate airway hyperresponsiveness (AHR). Inflammatory cell influx was enumerated in the bronchoalveolar lavage fluid (BALF) followed by lung histology. Additionally, the concentrations of Th2 and pro-inflammatory cytokines was assessed in the BALF by multiplexed immune assay. The mRNA expression of pro-inflammatory cytokines and Mucin 5AC (MUC5AC) was also evaluated in the lung. RESULTS: HPTLC fingerprinting and UHPLC quantification of Bronchom revealed the presence of bioactive phytometabolites, namely, rosmarinic acid, gallic acid, methyl gallate, piperine, eugenol and glycyrrhizin. Bronchom effectively reduced AHR driven by HDM-CFA and the influx of total leukocytes, eosinophils and neutrophils in the BALF. In addition, Bronchom inhibited the infiltration of inflammatory cells in the lung as well as goblet cell metaplasia. Further, it also suppressed the elevated levels of Th2 cytokines and pro-inflammatory cytokines in the BALF. Similarly, Bronchom also regulated the mRNA expression of pro-inflammatory cytokines as well as MUC5AC in mice lungs. Reduced effectiveness of a high dose of the steroid, dexamethasone was observed in the model. CONCLUSIONS: We have demonstrated for the first time the robust pharmacological effects of an herbo-mineral medicine in an animal model of mixed granulocytic asthma induced by HDM and CFA. The outcomes suggest the potential utility of Bronchom in severe asthmatics with a mixed granulocytic phenotype.

Protein-Protein interactive networks identified in bronchoalveolar lavage of severe compared to nonsevere asthma.

INTRODUCTION: Previous bronchoalveolar lavage fluid (BALF) proteomic analysis has evaluated limited numbers of subjects for only a few proteins of interest, which may differ between asthma and normal controls. Our objective was to examine a more comprehensive inflammatory biomarker panel in quantitative proteomic analysis for a large asthma cohort to identify molecular phenotypes distinguishing severe from nonsevere asthma. METHODS: Bronchoalveolar lavage fluid from 48 severe and 77 nonsevere adult asthma subjects were assessed for 75 inflammatory proteins, normalized to BALF total protein concentration. Validation of BALF differences was sought through equivalent protein analysis of autologous sputum. Subjects' data, stratified by asthma severity, were analysed by standard statistical tests, principal component analysis and 5 machine learning algorithms. RESULTS: The severe group had lower lung function and greater health care utilization. Significantly increased BALF proteins for severe asthma compared to nonsevere asthma were fibroblast growth factor 2 (FGF2), TGFα, IL1Ra, IL2, IL4, CCL8, CCL13 and CXCL7 and significantly decreased were platelet-derived growth factor a-a dimer (PDGFaa), vascular endothelial growth factor (VEGF), interleukin 5 (IL5), CCL17, CCL22, CXCL9 and CXCL10. Four protein differences were replicated in sputum. FGF2, PDGFaa and CXCL7 were independently identified by 5 machine learning algorithms as the most important variables for discriminating severe and nonsevere asthma. Increased and decreased proteins identified for the severe cluster showed significant protein-protein interactions for chemokine and cytokine signalling, growth factor activity, and eosinophil and neutrophil chemotaxis differing between subjects with severe and nonsevere asthma. CONCLUSION: These inflammatory protein results confirm altered airway remodelling and cytokine/chemokine activity recruiting leukocytes into the airways of severe compared to nonsevere asthma as important processes even in stable status.

Immunoglobulin free light chains in severe asthma patient: Could they be a new biomarker?

BACKGROUND: Increasing evidence is available about the presence of increased serum concentration of immunoglobulin (Ig) free light chains (FLCs) in both atopic and non-atopic inflammatory diseases, including severe asthma, providing a possible new biomarker of disease. METHODS: We analyzed clinical and laboratory data, including FLCs, obtained from a cohort of 79 asthmatic subjects, clinically classified into different GINA steps. A control group of 40 age-matched healthy donors (HD) was considered. Particularly, HD have been selected according to the absence of monoclonal components (in order to exclude paraproteinemias), were tested for total IgE (that were in the normal ranges) and were negative for aeroallergens specific IgE. Moreover, no abnormality of common inflammatory markers (i.e., erythrocyte sedimentation rate and C-reactive protein) was detectable. RESULTS: FLC-k levels were significantly increased in the asthmatic population, compared to the control group. Despite the absence of statistically significant differences in FLC-λ levels, the FLC-k/FLC-λ ratio displayed remarkable differences between the two groups. A positive correlation between FLC-κ and FLC-λ levels was found. FLC- λ level displayed a significant negative correlation with the FEV1 value. Moreover, the FLC-κ /FLC- λ ratio was negatively correlated with the SNOT-22 score and a positive correlation was observed between FLCs and Staphylococcus Aureus IgE enterotoxins sensitization. CONCLUSIONS: Our findings confirmed the role of FLCs in asthma as a potential biomarker in an inflammatory disease characterized by different endotypes and phenotypes. In particular, FLC-κ and FLC-k/FLC-λ ratio could be a qualitative indicator for asthma, while FLC-λ levels could be a quantitative indicator for clinical severity parameters.

Real-world biologics response and super-response in the International Severe Asthma Registry cohort.

BACKGROUND: Biologic asthma therapies reduce exacerbations and long-term oral corticosteroids (LTOCS) use in randomized controlled trials (RCTs); however, there are limited data on outcomes among patients ineligible for RCTs. Hence, we investigated responsiveness to biologics in a real-world population of adults with severe asthma. METHODS: Adults in the International Severe Asthma Registry (ISAR) with ≥24 weeks of follow-up were grouped into those who did, or did not, initiate biologics (anti-IgE, anti-IL5/IL5R, anti-IL4/13). Treatment responses were examined across four domains: forced expiratory volume in 1 second (FEV1) increase by ≥100 mL, improved asthma control, annualized exacerbation rate (AER) reduction ≥50%, and any LTOCS dose reduction. Super-response criteria were: FEV1 increase by ≥500 mL, new well-controlled asthma, no exacerbations, and LTOCS cessation or tapering to ≤5 mg/day. RESULTS: 5.3% of ISAR patients met basic RCT inclusion criteria; 2116/8451 started biologics. Biologic initiators had worse baseline impairment than non-initiators, despite having similar biomarker levels. Half or more of initiators had treatment responses: 59% AER reduction, 54% FEV1 increase, 49% improved control, 49% reduced LTOCS, of which 32%, 19%, 30%, and 39%, respectively, were super-responses. Responses/super-responses were more frequent in biologic initiators than in non-initiators; nevertheless, ~40-50% of initiators did not meet response criteria. CONCLUSIONS: Most patients with severe asthma are ineligible for RCTs of biologic therapies. Biologics are initiated in patients who have worse baseline impairments than non-initiators despite similar biomarker levels. Although biologic initiators exhibited clinical responses and super-responses in all outcome domains, 40-50% did not meet the response criteria.

Prediction of Clinical Response to Dupilumab in Patients with Severe Asthma Using Fractional Exhaled Nitric Oxide Combined with Pulmonary Function Testing.

INTRODUCTION: This study aimed to assess the effectiveness of fractional exhaled nitric oxide (FeNO) combined with pulmonary function testing (PFT) for predicting the treatment outcome of patients with severe asthma receiving dupilumab. METHODS: A total of 31 patients with severe asthma visiting our hospital from January 2022 to June 2023 were included in this study, with 28 patients completing a 16-week course of dupilumab treatment. Baseline clinical data, including demographic information, blood eosinophil counts, serum IgE levels, FeNO, asthma control test (ACT), asthma control questionnaire (ACQ), and other parameters, were collected. A predictive model using a generalized linear model was established. RESULTS: Following the 16-week course of dupilumab treatment, 22 patients showed effective response based on GETE scores, while 6 patients were nonresponders. Notably, significant improvements were observed in clinical parameters such as blood eosinophil counts, serum IgE levels, FeNO, FEV1, FEV1%, ACT, and ACQ in both response groups (p < 0.05). FeNO and pulmonary function tests demonstrated AUC values of 0.530, 0.561, and 0.765, respectively, in predicting the clinical efficacy of dupilumab, which were lower than when FeNO was combined with FEV1%. The combination of FeNO and FEV1% had a sensitivity of 1.000 and specificity of 0.591 in predicting treatment response. CONCLUSION: The combined assessment of FeNO and FEV1% provides improved accuracy for predicting the clinical efficacy of dupilumab in managing severe asthma. However, further larger scale clinical studies with comprehensive follow-up data are needed to validate the therapeutic efficacy and applicability across diverse patient populations.

COBRAPed cohort: Do sensitization patterns differentiate children with severe asthma from those with a milder disease?

BACKGROUND: It is unclear whether sensitization patterns differentiate children with severe recurrent wheeze (SRW)/severe asthma (SA) from those with non-severe recurrent wheeze (NSRW)/non-severe asthma (NSA). Our objective was to determine whether sensitization patterns can discriminate between children from the French COBRAPed cohort with NSRW/NSA and those with SRW/SA. METHODS: IgE to 112 components (c-sIgE) (ImmunoCAP® ISAC) were analyzed in 125 preschools (3-6 years) and 170 school-age children (7-12 years). Supervised analyses and clustering methods were applied to identify patterns of sensitization among children with positive c-sIgE. RESULTS: We observed c-sIgE sensitization in 51% of preschool and 75% of school-age children. Sensitization to house dust mite (HDM) components was more frequent among NSRW than SRW (53% vs. 24%, p < .01). Sensitization to non-specific lipid transfer protein (nsLTP) components was more frequent among SA than NSA (16% vs. 4%, p < .01) and associated with an FEV1/FVC < -1.64 z-score. Among sensitized children, seven clusters with varying patterns were identified. The two broader clusters identified in each age group were characterized by "few sensitizations, mainly to HDM." One cluster (n = 4) with "multiple sensitizations, mainly to grass pollen, HDM, PR-10, and nsLTP" was associated with SA in school-age children. CONCLUSIONS: Although children with wheeze/asthma display frequent occurrences and high levels of sensitization, sensitization patterns did not provide strong signals to discriminate children with severe disease from those with milder disease. These results suggest that the severity of wheeze/asthma may depend on both IgE- and non-IgE-mediated mechanisms.

Aerobic physical training reduces severe asthma phenotype involving kinins pathway.

INTRODUCTION: Aerobic physical training (APT) reduces eosinophilic airway inflammation, but its effects and mechanisms in severe asthma remain unknown. METHODS: An in vitro study employing key cells involved in the pathogenesis of severe asthma, such as freshly isolated human eosinophils, neutrophils, and bronchial epithelial cell lineage (BEAS-2B) and lung fibroblasts (MRC-5 cells), was conducted. Additionally, an in vivo study using male C57Bl/6 mice, including Control (Co; n = 10), Trained (Exe; n = 10), house dust mite (HDM; n = 10), and HDM + Trained (HDM + Exe; n = 10) groups, was carried out, with APT performed at moderate intensity, 5x/week, for 4 weeks. RESULTS: HDM and bradykinin, either alone or in combination, induced hyperactivation in human neutrophils, eosinophils, BEAS-2B, and MRC-5 cells. In contrast, IL-10, the primary anti-inflammatory molecule released during APT, inhibited these inflammatory effects, as evidenced by the suppression of numerous cytokines and reduced mRNA expression of the B1 receptor and ACE-2. The in vivo study demonstrated that APT decreased bronchoalveolar lavage levels of bradykinin, IL-1ß, IL-4, IL-5, IL-17, IL-33, TNF-α, and IL-13, while increasing levels of IL-10, klotho, and IL-1RA. APT reduced the accumulation of polymorphonuclear cells, lymphocytes, and macrophages in the peribronchial space, as well as collagen fiber accumulation, epithelial thickness, and mucus accumulation. Furthermore, APT lowered the expression of the B1 receptor and ACE-2 in lung tissue and reduced bradykinin levels in the lung tissue homogenate compared to the HDM group. It also improved airway resistance, tissue resistance, and tissue damping. On a systemic level, APT reduced total leukocytes, eosinophils, neutrophils, basophils, lymphocytes, and monocytes in the blood, as well as plasma levels of IL-1ß, IL-4, IL-5, IL-17, TNF-α, and IL-33, while elevating the levels of IL-10 and IL-1RA. CONCLUSION: These findings indicate that APT inhibits the severe asthma phenotype by targeting kinin signaling.

Clinical remission maintained and improved over time in patients with severe asthma treated with omalizumab.

BACKGROUND: Clinical remission has recently been proposed as a possible treatment goal even in severe asthma. In this real-world study, we aimed to assess the achievement rate and predictive factors of clinical remission using omalizumab in patients with severe asthma. METHODS: This retrospective observational study included patients with severe asthma initiated with omalizumab therapy and recruited from the asthma clinic of the Akdeniz University Hospital, Turkey. Clinical remission was defined as patients who received no oral corticosteroid (OCS) therapy; showed no exacerbations; showed an asthma control questionnaire score of ≤ 1, asthma control test (ACT) of ≥ 20, or both and, FEV1 of ≥ 80% predicted. RESULTS: A total of 58 patients were included in the study, with an average age of 56.4 ± 13.6 years. The mean duration of asthma was 23.5 ± 11.8 years and the mean duration of omalizumab treatment was 80.05 ± 35.04 months. Clinical remission rates were 25.9% in the first and second year, 34.0% in the third year, 34.1% in the fourth year and 47.4% in the fifth year. Pre-omalizumab ACT, FEV1 (%) and OCS use were significantly higher in patients with clinical remission at 1 year. Logistic regression analyses showed that none of the factors predicted clinical remission. CONCLUSION: Omalizumab has the potential to induce disease remission in a significant proportion of people with severe asthma, and this is maintained and improved over time.

Digitally monitored inhaled therapy: a 'smart' way to manage severe asthma?

INTRODUCTION: One of the fundamental challenges of managing patients with severe asthma is treatment adherence, particularly with inhaled corticosteroids. Adherence is difficult to measure objectively and poor adherence is associated with worse outcomes. In this study, assess the ability of a 'smart' inhaler to record adherence in severe asthma patients and measure the impact of this on asthma control. METHODS: Consecutive consenting patients meeting criteria for biologics had their existing high-dose ICS/LABA//LAMA combination inhaler/s switched to mometasone/indacaterol/glycopyrronium (114/46/136). Routine clinical data, including blood eosinophils, FeNO, and ACQ-6 scores were collected at baseline and at 4 wk. Adherence was then checked on the Propeller Health app, and good adherence was defined as >80% of prescribed usage. Participants were then followed-up at 12 months to record the proportion of patients who were initiated on biologics. RESULTS: 77 patients (mean [SD] age = 50.4 [15.7] years, 67.5% female [n = 52]) participated. 71 participants were able to use the device and 65% (n = 46) of these attained good asthma control and were not initiated on biologics at 12-month follow-up. Both groups demonstrated a significant reduction in ACQ6 score at follow-up (2.81 vs. 1.92, p < 0.001 and 3.05 vs. 2.60, p < 0.001, respectively), but there was no statistically significant difference in improvement between groups. Patients with optimal adherence also demonstrated a significant reduction in median FeNO at follow-up (47 ppb vs. 40 ppb, p = 0.003). CONCLUSIONS: In severe asthma patients, 'smart' inhalers may represent an effective management tool to improve adherence and asthma control, therefore avoiding the need for patients to commence biological therapies.

Real-world clinical remission of severe asthma with benralizumab in Spanish adults with severe asthma.

OBJECTIVE: Patients with severe eosinophilic asthma experience high risk of exacerbations and reduced quality of life. Benralizumab, a monoclonal antibody binding to IL-5 receptor α subunit, is an approved drug for its treatment. The objective was to describe clinical remission after benralizumab prescription in routine clinical practice. METHODS: Retrospective multicenter study with data from four hospitals in Valencian Community (Spain) with asthma units between 2019 and 2020. Data was gathered at baseline and after 12 months. We considered clinical remission after 1 year if the patient remained without exacerbations and use of systemic corticosteroids and with good clinical control and normal lung function. RESULTS: Data from 139 patients was gathered. At the 12-month follow-up, 44.1% were in clinical remission, since 84.0%, 77.5%, 51.0% and 95.5% of patients did not experience exacerbations, had total asthma control test score of ≥20, prebronchodilator FEV1 of ≥80% and did not use systemic corticosteroids. A significant reduction of long-acting muscarinic antagonists (p = 0.0001), leukotriene receptor antagonists (p = 0.0326), oral corticosteroids (p < 0.0001) and short-acting beta agonists (p = 0.0499) was observed. Baseline factors with greatest individual influence on clinical remission were employment situation, tobacco use, comorbidity number, eosinophil value, number of exacerbations, FEV1, emergency visit number, and ACT, MiniAQLQ and TAI scores. Final analysis of multiple logistic regression indicated that having baseline FEV1 value below 80% increases remission chance 9.7 times a year compared to FEV1 >80%. CONCLUSION: Clinical remission after treatment with benralizumab is achievable in a high percentage of patients with severe asthma eosinophilia not controlled in real life.

Mepolizumab in children and adolescents with severe eosinophilic asthma not eligible for omalizumab: a single Center experience.

BACKGROUND: Mepolizumab is an anti-interleukin-5 monoclonal antibody shown to reduce asthma exacerbations in adults and adolescents with severe eosinophilic asthma. AIM: To assess the impact of mepolizumab on children and adolescents over 12 months by examining steroid usage, asthma-related hospitalizations, Asthma Control Test (ACT) scores, fractional exhaled nitric oxide concentration (FeNO), forced expiratory volume in 1 s (FEV1), mid expiratory flow (FEF25-75%), and blood eosinophil count. METHODS: Retrospective analysis performed between October 2015 and December 2022. Data was reviewed 12 months before and after commencing mepolizumab. Mepolizumab was offered if the patient had severe eosinophilic asthma and were unresponsive to or ineligible for omalizumab. RESULTS: Sixteen participants (age 7-17, 8 males, 8 females) received subcutaneous mepolizumab monthly with no serious adverse reactions. Incidence of hospital admissions fell significantly (IRR 0.33, p = 0.007). Among the 11 patients receiving daily oral corticosteroids, 3 were weaned off daily oral steroids and 3 patients' daily dose was significantly reduced (mean Δ-0.095 ± 0.071 mg/kg, p = 0.0012). Eosinophil count was decreased (mean Δ-0.85 x 109/L, p < 0.001). There was no significant change in mean overall steroid burden per patient (mean Δ-1445.63 ± 1603.18 mg, p = 0.10), ACT scores (mean Δ2.88 ± 6.71, p = 0.17), FEV1 z-scores (mean Δ-0.99 ± 1.88, p = 0.053), FEF25-75% z-scores (mean Δ-0.65 ± 1.61, p = 0.13), FeNO (mean Δ-20.09 ± 80.86, p = 0.34), or number of courses of oral steroids given for asthma attacks (IRR 0.71, p = 0.09). CONCLUSION: Among children and adolescents with severe eosinophilic asthma ineligible for or not responsive to omalizumab, mepolizumab therapy exhibited significant reduction in rate of asthma-related hospitalizations and significant decrease in daily steroid dosage.