Pretreatment circulating MAIT cells, neutrophils, and periostin predicted the real-world response after 1-year mepolizumab treatment in asthmatics.

BACKGROUND: Mepolizumab treatment improves symptom control and quality of life and reduces exacerbations in patients with severe eosinophilic asthma. However, biomarkers that predict therapeutic effectiveness must be determined for use in precision medicine. Herein, we elucidated the dynamics of various parameters before and after treatment as well as patient characteristics predictive of clinical responsiveness to mepolizumab after 1-year treatment. METHODS: Twenty-seven patients with severe asthma were treated with mepolizumab for one year. Asthma control test scores, pulmonary function tests, fractional exhaled nitric oxide levels, and blood samples were evaluated. Additionally, we explored the role of CD69-positive mucosal-associated invariant T (MAIT) cells as a candidate biomarker for predicting treatment effectiveness by evaluating an OVA-induced asthma murine model using MR1 knockout mice, where MAIT cells were absent. RESULTS: The frequencies of CD69-positive group 1 innate lymphoid cells, group 3 innate lymphoid cells, natural killer cells, and MAIT cells decreased after mepolizumab treatment. The frequency of CD69-positive MAIT cells and neutrophils was lower and serum periostin levels were higher in responders than in non-responders. In the OVA-induced asthma murine model, CD69-positive MAIT cell count in the whole mouse lung was significantly higher than that in the control mice. Moreover, OVA-induced eosinophilic airway inflammation was exacerbated in the MAIT cell-deficient MR1 knockout mice. CONCLUSIONS: This study shows that circulating CD69-positive MAIT cells, neutrophils, and serum periostin might predict the real-world response after 1-year mepolizumab treatment. Furthermore, MAIT cells potentially have a protective role against type 2 airway inflammation.

Histological characteristics of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinases-1 in asthmatic murine model during A(H1N1)pdm09 infection.

Pandemic influenza virus A(H1N1)pdm09 infection occurred in healthy children and young adults, but asthmatic patients presented more rapid progression of respiratory distress and plastic bronchitis. To investigate the pathogenesis of worsening respiratory symptoms after A(H1N1)pdm09 infection, we focused on matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1). MMP-9 and TIMP-1 levels in bronchoalveolar lavage fluid and serum from mice with and without asthma were evaluated after A(H1N1)pdm09 or seasonal A(H1N1) infection. MMP-9 levels were more elevated in Asthma/A(H1N1)pdm09-infected mice than in non-Asthma/A(H1N1)pdm09-infected mice on both 3 and 7 days post-infection. Immunohistochemical findings in this pneumonia model showed that MMP-9 and TIMP-1 positive cells were observed in blood vessels and bronchus of lung tissue in severe pathological findings of pneumonia with asthma. Microscopically, shedding cells and secretions were conspicuous in the trachea on days 3 and 7 post-infection, in the A(H1N1)pdm09-infected mice with asthma. Our results suggest that MMP-9 and TIMP-1 expressions are related to severe pneumonia in the A(H1N1)pdm09 infection with asthma, leading to cause epithelial cell shedding.

Chitin induces steroid-resistant airway inflammation and airway hyperresponsiveness in mice.

BACKGROUND: Previous reports have shown that pathogen-associated patterns (PAMPs) induce the production of interleukin (IL)-1ß in macrophages. Moreover, studies using mouse models also suggest that chitin, which acts as a PAMP, induces adjuvant effects and eosinophilic infiltration in the lung. Thus, we investigated the effects of inhaled chitin in mouse models. METHODS: We developed mouse models of inhaled chitin particle-induced airway inflammation and steroid-resistant ovalbumin (OVA)-induced airway inflammation. Some experimental groups of mice were treated additionally with dexamethasone (DEX). Murine alveolar macrophages (AMs), which were purified from bronchoalveolar lavage (BAL) fluids, were incubated with chitin, and treated with or without DEX. RESULTS: The numbers of total cells, AMs, lymphocytes, eosinophils, and neutrophils among BAL-derived cells, as well as the IL-1ß levels in BAL fluids and the numbers of IL-1ß-positive cells in lung, were significantly increased by chitin stimulation. Airway hyperresponsiveness (AHR) was aggravated in mice of the chitin inflammation model compared to control animals. The production of IL-1ß was significantly increased in murine AMs by chitin treatment, but DEX administration did not inhibit this chitin-induced IL-1ß production. Furthermore, in mouse models, DEX treatment inhibited the OVA-induced airway inflammation and AHR but not the airway inflammation and AHR induced by chitin or the combination of OVA and chitin. CONCLUSIONS: These results suggest that inhaled chitin induces airway inflammation, AHR, and the production of IL-1ß. Furthermore, our findings demonstrate for the first time that inhaled chitin induces steroid-resistant airway inflammation and AHR. Inhaled chitin may contribute to features of steroid-resistant asthma.

Using fractional exhaled nitric oxide to guide step-down treatment decisions in patients with asthma: a systematic review and individual patient data meta-analysis.

BACKGROUND: High exhaled nitric oxide fraction (F ENO) levels are associated with greater risk of asthma exacerbation. However, it is not clear how F ENO can be used to guide safe reductions in inhaled corticosteroid (ICS) doses in asthma patients. This study assesses the ability of F ENO to guide ICS reductions. METHODS: Systematic searching of electronic databases identified prospective observational studies and randomised controlled trials which recruited participants with mild-to-moderate asthma aged ≥12 years and measured F ENO before reducing ICS. We performed multilevel mixed-effects logistic regression in relation to acute exacerbations and estimated each participant's exacerbation risk using our logistic regression model. RESULTS: We included data from seven out of eight eligible studies, representing 384 participants. ICS doses were halved in four studies and withdrawn in three studies. A baseline F ENO measurement of ≥50 ppb was associated with increased risk of exacerbations (crude OR 3.14, 95% CI 1.41-7.00, p=0.005; adjusted OR 3.08, 95% CI 1.36-6.98, p=0.007) and corresponded to an estimated exacerbation risk cut-off of 15%. Reducing ICS when estimated exacerbation risk was <15% versus <10% would result in fewer patients remaining on the same ICS dose (40 (10.4%) out of 384 versus 141 (36.7%) out of 384), but similar proportions of patients avoiding exacerbations (222 (91.4%) out of 243, 95% CI 87.1-94.6% versus 311 (90.4%) out of 344, 95% CI 86.8-93.3%). CONCLUSION: In patients with mild-to-moderate asthma, gradual ICS reduction when F ENO is <50 ppb may help decrease ICS use without increasing exacerbations. Future research should aim to validate these findings in larger populations.

Mobile Health App for Japanese Adult Patients With Asthma: Clinical Observational Study.

BACKGROUND: Inappropriate asthma control reduces quality of life and causes increased exacerbations. Mobile health (mHealth) employs information and communication technology for surveying health-related issues. OBJECTIVE: This noninterventional, observational study assessed current real-world asthma control levels among Japanese patients with asthma and cough variant asthma (CVA) using the Zensoku-Log app. METHODS: We developed the app using the ResearchKit platform and conducted a mobile-based, self-reporting, observational survey among patients with asthma and CVA. The app was downloaded 7855 times between February 2016 and February 2018, and enabled collection of data on symptoms, comorbidities, quality of life, medications, asthma control, and adherence. RESULTS: Of the 1744 eligible participants (median age 33 years; range 20-74 years; male-to-female ratio 38.7:61.3), 50.97% (889/1744) reported unscheduled visits, 62.84% (1096/1744) reported regularly scheduled visits, 23.14% (402/1737) smoked, and 40.75% (705/1730) had pets. In addition, 91.89% (1598/1739) of participants had atopic predisposition, including allergic rhinitis and atopic dermatitis. Daily inhaled corticosteroid and oral corticosteroid treatment had been prescribed for 89.45% (1552/1735) and 22.07% (383/1735) of participants, respectively. Although an asthma control questionnaire demonstrated poor asthma control in 58.48% (1010/1727), a leukotriene receptor antagonist, theophylline, and a long-acting muscarinic antagonist had been prescribed for only 30.66% (532/1735), 15.91% (276/1735), and 4.38% (76/1735), respectively. The Adherence Starts with Knowledge 12 total score was 29. In the 421 participants who repeated the questionnaire, asthma control increased significantly between the initial and last rounds (P=.002). CONCLUSIONS: Users of this mHealth app in Japan had poorly controlled asthma and may need more treatment for asthma and their comorbidities. Repeated app users demonstrated improved asthma control. TRIAL REGISTRATION: UMIN Clinical Trial Registry UMIN000021043; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000023913.

Difference between two exhaled nitric oxide analyzers, NIOX VERO® electrochemical hand-held analyzer and NOA280i® chemiluminescence stationary analyzer.

BACKGROUND: Fractional exhaled nitric oxide (FENO) is useful for the evaluation of eosinophilic airway inflammation, including that seen in asthma. Although a new electrochemical hand-held FENO analyzer, the NIOX VERO® (Aerocrine AB, Solna, Sweden), is clinically convenient to use, it has not been fully compared with the chemiluminescence stationary electrochemical analyzer NOA280i® (Sievers Instruments, Boulder, CO, USA) in terms of the level of measured FENO. The aim of this study was to determine whether there is a difference between the two analyzers. METHODS: The FENO levels measured with both NIOX VERO® and NOA280i® were evaluated in 1,369 adults at Juntendo University Hospital from May 2016 to October 2016. RESULTS: The median FENO level measured with the NIOX VERO® was significantly lower than that measured with the NOA280i® (41 ppb, range 5-368 ppb vs. 29 ppb, range 5-251 ppb; p < 0.001). There was a strong positive correlation in the measurement of FENO level between the NOA280i® and the NIOX VERO® (r = 0.942, p < 0.001). The following conversion equation was calculated: FENO (NOA280i®) = 1.362 (SE, 0.661) + 1.384 (SE, 0.021) × FENO (NIOX VERO®). CONCLUSIONS: To our best knowledge, we have provided the first report showing that the measured FENO level with the NIOX VERO® was approximately 30% lower than that with the NOA280i® and that there was a significant correlation between the measurements of these two devices. The correction equation that we provided may help assess the data obtained by these two analyzers. Abbreviations ATS American Thoracic Society BMI Body mass index ERS European Respiratory Society FENO Fractional exhaled nitric oxide GINA Global Initiative for Asthma NO Nitric oxide ppb Parts per billion ROC Receiver operating characteristic SD Standard deviation.

Combination of TWEAK and TGF-ß1 induces the production of TSLP, RANTES, and TARC in BEAS-2B human bronchial epithelial cells during epithelial-mesenchymal transition.

AIM OF THE STUDY: In patients with asthma, chronic inflammatory processes and the subsequent remodeling of the airways contribute to the symptoms and the pathophysiological changes. Epithelial-mesenchymal transition (EMT) is thought to play an important role in tissue remodeling. Previous reports show that tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a cytokine of the TNF superfamily, exerts pro-inflammatory effects, and enhances transforming growth factor (TGF)-ß-induced EMT in bronchial epithelial cells. In this study, we investigated the TWEAK-induced cytokine and chemokine production in the human bronchial epithelial cell line BEAS-2B during EMT. MATERIALS AND METHODS: Quantitative real-time RT-PCR, enzyme-linked immunosorbent assays, western blotting, and immunohistochemistry were used to define the production of cytokines and chemokines. RESULTS: We found that TWEAK increases mRNA and protein levels of thymic stromal lymphopoietin (TSLP), monocyte chemoattractant protein -1 (MCP-1), regulated upon activation normal T cell express sequence (RANTES), and IL-8 in BEAS-2B bronchial epithelial cells. Moreover, co-treatment with TWEAK and TGF-ß1 induces not only features of EMT but also enhances the production of TSLP and RANTES. Thymus- and activation-regulated chemokines (TARC) production is induced by the co-treatment of TWEAK and TGF-ß1 but not by TWEAK or TGF-ß1 stimulation alone. Furthermore, the increased mRNA expression of TSLP and RANTES after co-treatment with TWEAK and TGF-ß1 is prevented by inhibitors of Smad-independent signaling pathways. CONCLUSIONS: In the present study, we have revealed a novel mechanism for the production of asthma-related cytokines and chemokines in EMT driven by the co-stimulation with TWEAK and TGF-ß1. We conclude that cellular EMT processes caused by TWEAK and TGF-ß1 may contribute to chronic airway inflammation and remodeling.

Assessing usability of the "Adherence Starts with Knowledge 20" (ASK-20) questionnaire for Japanese adults with bronchial asthma receiving inhaled corticosteroids long term.

BACKGROUND: Maintaining high treatment adherence levels is critical for effective management of chronic diseases. The Adherence Starts with Knowledge 20 (ASK-20) questionnaire is the only linguistically validated patient-reported treatment adherence tool available in Japan. We conducted additional analyses on ASK-20 data from Japanese adults with asthma. METHODS: This was a prospective, non-interventional, single-visit, multi-centre study in Japanese adults (n = 300) with asthma receiving long-term treatment with inhaled corticosteroids (ICS) or ICS/long-acting beta-agonists. We tested the reliability, validity and the relationship between different adherence conditions and ASK-20 score. At one centre, ICS adherence prescription rate was calculated retrospectively based on 2-year percentage ICS adherence data contained within medical records. RESULTS: The ASK-20 had good internal consistency reliability (Cronbach's alpha = 0.76; n = 290). Discriminant validity was demonstrated with significant correlations between the percentage ICS adherence rates and both the mean ASK-20 total score and mean total barrier count (TBC) (r = -0.51 and -0.58, p < 0.001; n = 111). The ASK-20 total score discriminated between subjects with good and poor adherence measured by patients' reported questionnaire and between those of high and low percentage ICS adherence rates. All other factors that possibly affect adherence were correlated with the mean ASK-20 total score and mean TBC in addition to the number of medicines taken every day. CONCLUSIONS: The Japanese ASK-20 is a reliable tool for assessing possible medication adherence barriers and adherence behaviour in Japanese adults with asthma. Furthermore, our results are comparable with those obtained using the ASK-20 in the United States.

Circulating activated innate lymphoid cells and mucosal-associated invariant T cells are associated with airflow limitation in patients with asthma.

BACKGROUND: A variety of innate subsets of lymphoid cells such as natural killer (NK) cells, several populations of innate lymphoid cells (ILCs), and mucosal-associated invariant T (MAIT) cells as innate-like T lymphocytes are involved in asthma and may have important effector functions in asthmatic immune responses. In the present study, we investigated whether NK cells, ILCs, and MAIT cells in the peripheral blood of patients with asthma would be associated with clinical asthma parameters. METHODS: We recruited 75 adult patients with mild to severe asthma. The peripheral blood mononuclear cells in peripheral venous blood samples from the patients were purified and stained with different combinations of appropriate antibodies. The cells were analyzed by flow cytometry. RESULTS: The percentage of activated (i.e., CD69+) NK cells in the total NK cell population was negatively correlated with FEV1% which is calculated by the forced expiratory volume in 1 s (FEV1)/the forced vital capacity (FVC). The percentages of CD69+ ILC1s and ILC2s were negatively correlated with FEV1% and %FEV1. The percentage of CD69+ ILC3s was positively correlated with BMI, and the percentage of CD69+ MAIT cells was negatively correlated with FEV1%. Moreover, the percentage of CD69+ NK cells, ILC1s, ILC2s, ILC3s, and MAIT cells were positively correlated with each other. CONCLUSIONS: For the first time, our data showed that activated NK cells, ILC1s, ILC2s, ILC3s, and MAIT cells were positively correlated with each other and may be associated with airflow limitation in patients with asthma.

Evaluation of switching low-dose inhaled corticosteroid to pranlukast for step-down therapy in well-controlled patients with mild persistent asthma.

OBJECTIVE: Treatment guidelines for asthma recommend step-down therapy for well-controlled asthma patients. However, the precise strategy for step-down therapy has not been well defined. We investigated whether well-controlled patients with mild persistent asthma can tolerate a step-down therapy of either a reduced dose of inhaled corticosteroid (ICS) or a switch to a leukotriene receptor antagonist (LTRA), pranlukast hydrate. METHODS: We recruited 40 adult patients with mild persistent asthma who were well-controlled for at least 3 months with a low-dose ICS therapy. The patients were randomly assigned to either an ICS dose reduction or a switch to pranlukast for 6 months. RESULTS: FeNO levels in the pranlukast group were significantly increased over that in the ICS group. There were no significant differences between the two groups for lung function, FOT, at the endpoint. The percentage of patients with controlled asthma was 72.2% in the pranlukast group and 90% in the ICS group. No statistically significant difference between the two groups in the percentages of patients with treatment failure was observed. CONCLUSIONS: Patients with mild persistent asthma that is well-controlled by a low dose of ICS can be switched to pranlukast safely for at least 6 months. However, 27.8% of the pranlukast group failed to maintain well-control, and FeNO levels increased with the switch to pranlukast at 6 months. This study was been limited by the small sample size and should therefore be considered preliminary. Further studies are needed to investigate the therapeutic efficacy of LTRA monotherapy as a step-down therapy.

TWEAK enhances TGF-ß-induced epithelial-mesenchymal transition in human bronchial epithelial cells.

BACKGROUND: Chronic airway inflammatory disorders, such as asthma, are characterized by airway inflammation and remodeling. Chronic inflammation and damage to the airway epithelium cause airway remodeling, which is associated with improper epithelial repair, and is characterized by elevated expression of transforming growth factor-ß (TGF-ß). Epithelial-mesenchymal transition (EMT) is an important mechanism during embryonic development and tissue remodeling whereby epithelial cells gain the capacity to increase motility by down-regulation of epithelial markers and up-regulation of mesenchymal markers. TGF-ß is a central inducer of EMT, and TGF-ß-induced EMT is enhanced by pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-1ß. We investigated whether the pro-inflammatory cytokine TWEAK (TNF-like weak inducer of apoptosis) enhanced TGF-ß1-induced EMT in the human bronchial epithelial cell line BEAS-2B. METHODS: Quantitative RT-PCR and western blotting were used to define alterations in epithelial and mesenchymal marker expression in BEAS-2B cells. The cells were assessed for 48 h after stimulation with TGF-ß1 alone or in combination with TWEAK. RESULTS: TGF-ß1 induced spindle-like morphology and loss of cell contact, and reduced the expression of epithelial marker E-cadherin and increased the expression of mesenchymal markers N-cadherin and vimentin. Our data, for the first time, show that TWEAK reduced the expression of E-cadherin, and that co-treatment with TGF-ß1 and TWEAK enhanced the TGF-ß1-induced features of EMT. Moreover, hyaluronan synthase 2 expression was up-regulated by a combination with TGF-ß1 and TWEAK, but not TNF-α. We also demonstrated that the Smad, p38 MAPK, and NF-κB signaling pathways, and the transcriptional repressor ZEB2 might mediate N-cadherin up-regulation by TGF-ß1 in combination with TWEAK. CONCLUSIONS: These findings suggest that the pro-inflammatory cytokine TWEAK and TGF-ß1 have synergistic effects in EMT and may contribute to chronic airway changes and remodeling.

Characteristics of alveolar macrophages from murine models of OVA-induced allergic airway inflammation and LPS-induced acute airway inflammation.

BACKGROUND:  Macrophages include the classically activated pro-inflammatory M1 macrophages (M1s) and alternatively activated anti-inflammatory M2 macrophages (M2s). The M1s are activated by both interferon-γ and Toll-like receptor ligands, including lipopolysaccharide (LPS), and have potent pro-inflammatory activity. In contrast, Th2 cytokines activate the M2s, which are involved in the immune response to parasites, promotion of tissue remodeling, and immune regulatory functions. Although alveolar macrophages (AMs) play an essential role in the pulmonary immune system, little is known about their phenotypes. METHODS:  Quantitative reverse transcription polymerase chain reaction and flow cytometry were used to define the characteristics of alveolar macrophages derived from untreated naïve mice and from murine models of both ovalbumin (OVA)-induced allergic airway inflammation and LPS-induced acute airway inflammation. AMs were co-cultured with CD4(+) T cells and were pulsed with tritiated thymidine to assess proliferative responses. RESULTS:  We characterized in detail murine AMs and found that these cells were not completely consistent with the current M1 versus M2-polarization model. OVA-induced allergic and LPS-induced acute airway inflammation promoted the polarization of AMs towards the current M2-skewed and M1-skewed phenotypes, respectively. Moreover, our data also show that CD11c(+) CD11b(+) AMs from the LPS-treated mice play a regulatory role in antigen-specific T-cell proliferation in vitro. CONCLUSIONS:  These characteristics of AMs depend on the incoming pathogens they encounter and on the phase of inflammation and do not correspond to the current M1 versus M2-polarization model. These findings may facilitate an understanding of their contributions to the pulmonary immune system in airway inflammation.

Cytokine profile of bronchoalveolar lavage fluid from a mouse model of bronchial asthma during seasonal H1N1 infection.

BACKGROUND: Several studies support the role of viral infections in the pathogenesis of asthma exacerbation. However, several pediatricians believe that influenza virus infection does not exacerbate bronchial asthma, except for influenza A H1N1 2009 pandemic [A(H1N1)pdm09] virus infection. We previously reported that A(H1N1)pdm09 infection possibly induces severe pulmonary inflammation or severe asthmatic attack in a mouse model of bronchial asthma and in asthmatic children. However, the ability of seasonal H1N1 influenza (H1N1) infection to exacerbate asthmatic attacks in bronchial asthma patients has not been previously reported, and the differences in the pathogenicity profiles, such as cytokine profiles, remains unclear in bronchial asthma patients after A(H1N1)pdm09 and H1N1 infections. METHODS: The cytokine levels and viral titers in the bronchoalveolar lavage (BAL) fluid from mice with and without asthma after H1N1 infection (A/Yamagata and A/Puerto Rico strains) were compared. RESULTS: The interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, IL-5, interferon (IFN)-α, IFN-ß, and IFN-γ levels were significantly higher in the BAL fluids from the control/H1N1 mice than from the asthmatic/H1N1 mice. The viral titers in the BAL fluid were also significantly higher in the control/H1N1mice than in the asthmatic/H1N1 mice infected with either A/Yamagata or A/Puerto Rico. CONCLUSIONS: A(H1N1)pdm09 infection, but not H1N1 infection, can induce severe pulmonary inflammation through elevated cytokine levels in a mouse model of asthma.

Development of assay for determining free IgE levels in serum from patients treated with omalizumab.

BACKGROUND: Omalizumab, a monoclonal anti-IgE antibody, is currently indicated for the treatment of moderate-to-severe allergic asthma. To measure active IgE levels in sera from patients treated with omalizumab, the IgE subfraction in complex with omalizumab should be eliminated from total IgE, and free IgE levels can then be determined. With the aim of therapeutic monitoring for anti-IgE therapy, we developed a new ELISA for free IgE. METHODS: We used recombinant human soluble FcεRIα as a capture antigen and a biotinylated polyclonal anti-IgE antibody for detection. Using the newly developed ELISA, we measured the serum free IgE levels weekly in four asthmatic patients after their first omalizumab injection. We also measured the serum free IgE levels in 54 patients treated with omalizumab for over 4 weeks. RESULTS: This assay was technically robust, the mean recovery rate in serum was 93.16% ± 5.34%. For all patients, omalizumab treatment significantly reduced serum free IgE levels prior to the second omalizumab injection. To maintain the benefit of omalizumab, serum free IgE concentrations should be <50 ng/ml. However, in 14 of 54 patients treated with omalizumab for over 4 weeks, serum free IgE concentrations measured by our ELISA were >50 ng/ml. CONCLUSIONS: Our data suggest that the measurement of free IgE levels using our newly developed ELISA would be useful for monitoring serum free IgE levels during omalizumab therapy.

[Comparison of exhaled nitric oxide levels measured by two offline methods and the NO breath® method in Japan].

BACKGROUND: The fraction of exhaled nitric oxide (FeNO) is a useful marker of eosinophilic airway inflammation in asthmatics. Clinical application of FeNO measurement in Japan is expected increase because the procedure is now covered through health insurance. However, the measurement system used is known to affect FeNO results, and it remains unknown whether results from offline methods correlate with those from traditional online methods, such as NO breath®. METHODS: The study population comprised 48 patients at our hospital. FeNO levels were measured by using two offline methods (Sievers and CEIS) and a standard online method, NO breath® RESULTS: FeNONO breath levels were significantly correlated with FeNOSievers(r=0.875) and FeNOCEIS(r=0.888) levels. FeNONO breath levels were nearly equal to FeNOSievers results (FeNONO breath=1.05×FeNOSievers), but both of these levels were lower (p=0.02) than FeNOCEIS data (FeNONO breath=0.74×FeNOCEIS). A Bland-Altman plot of values obtained by the NO breath® and Sievers methods revealed that the NO breath® result was lower than the Sievers level when FeNO was low but was higher than the Sievers level when FeNO was high. CONCLUSION: Differences exist in the levels of FeNO measurement by three methods (two offline methods and NO breath®): conversion equations are needed to compare the FeNO levels obtained by using these three methods. In addition, NO breath® may be more useful to distinguish asthmatic patients from non-asthmatics, compared with Sievers method.

Prevalence and causes of chronic cough in Japan.

BACKGROUND: Chronic cough is one of the most common symptoms of respiratory diseases and can adversely affect patients' quality of life and interfere with social activities, resulting in a significant social burden. A survey is required to elucidate the frequency and treatment effect of chronic cough. However, clinical studies that cover all of Japan have not yet been conducted. METHODS: Patients who presented with a cough that lasted longer than 8 weeks and visited the respiratory clinics or hospitals affiliated with the Japan Cough Society during the 2-year study period were registered. RESULTS: A total of 379 patients were enrolled, and those who did not meet the definition of chronic cough were excluded. A total of 334 patients were analyzed: 201 patients had a single cause, and 113 patients had two or more causes. The main causative diseases were cough variant asthma in 92 patients, sinobronchial syndrome (SBS) in 36 patients, atopic cough in 31 patients, and gastroesophageal reflux (GER)-associated cough in 10 patients. The time required to treat undiagnosed patients and those with SBS was significantly longer and the treatment success rate for GER-associated cough was considerably poor. CONCLUSIONS: We confirmed that the main causes of chronic cough were cough variant asthma, SBS, atopic cough, and their complications. We also showed that complicated GER-associated cough was more likely to become refractory. This is the first nationwide study in Japan of the causes and treatment effects of chronic cough.

Analysis of bronchoalveolar lavage fluid in a mouse model of bronchial asthma and H1N1 2009 infection.

BACKGROUND: Bronchial asthma is known as a risk factor of admission to the intensive care unit. However, the mechanism by which pandemic 2009 H1N1 (A(H1N1)pdm09) infection increases the severity of symptoms in patients with bronchial asthma is unknown; therefore, we aimed at determining this mechanism. METHODS: Inflammatory cell levels in the bronchoalveolar lavage (BAL) fluid from the non-asthma/mock, non-asthma/A(H1N1)pdm09, asthma/mock, and asthma/A(H1N1)pdm09 groups were determined using BALB/c mice. Cell infiltration levels, cytokine levels, and viral titers were compared among the groups. RESULTS: Neutrophil, monocyte, interleukin (IL)-5, IL-6, IL-10, IL-13, and tumor necrosis factor (TNF)-α levels were significantly higher in the BAL fluid from the non-asthma/A(H1N1)pdm09 and asthma/A(H1N1)pdm09 groups than in the mock groups (p<0.05 for neutrophils and monocytes; p<0.01 for the rest). The number of eosinophils and CD8(+) lymphocytes and the level of transforming growth factor beta 1 (TGF-ß1) in BAL fluid in the asthma/A(H1N1)pdm09 group were significantly higher among all groups (p<0.05 for eosinophils and CD8(+) lymphocytes; p<0.01 for TGF-ß1). The levels of IL-6, IL-10, IL-13, and TNF-α were significantly higher in the asthma/A(H1N1)pdm09 group than in the non-asthma/A(H1N1)pdm09 group (p<0.05 for IL-6 and IL-10; p<0.01 for IL-13 and TNF-α). The level of IFN-γ in the asthma/A(H1N1)pdm09 group was significantly lower than that in the non-asthma/A(H1N1)pdm09 group (p<0.05). The viral titers in the BAL fluids were higher in the asthma/A(H1N1)pdm09 group than in the non-asthma/A(H1N1)pdm09 group (p<0.05). Histopathological examination showed more severe infiltration of inflammatory cells and destruction of lung tissue in the asthma/A(H1N1)pdm09 group than in the non-asthma/A(H1N1)pdm09 group. CONCLUSIONS: Severe pulmonary inflammation induced by elevated levels of cytokines, combined with increased viral replication due to decreased IFN-γ levels, may contribute to worsening respiratory symptoms in patients with bronchial asthma and A(H1N1)pdm09 infection.

Pretreatment Frequency of Circulating Th17 Cells and FeNO Levels Predicted the Real-World Response after 1 Year of Benralizumab Treatment in Patients with Severe Asthma.

Benralizumab treatment reduces exacerbations and improves symptom control and quality of life in patients with severe eosinophilic asthma. However, the determination of biomarkers that predict therapeutic effectiveness is required for precision medicine. Herein, we elucidated the dynamics of various parameters before and after treatment as well as patient characteristics predictive of clinical effectiveness after 1 year of benralizumab treatment in severe asthma in a real-world setting. Thirty-six patients with severe asthma were treated with benralizumab for 1 year. Lymphocyte subsets in peripheral blood samples were analyzed using flow cytometry. Treatment effectiveness was determined based on the ACT score, forced expiratory volume in 1 s (FEV1), and the number of exacerbations. Benralizumab provided symptomatic improvement in severe asthma. Benralizumab significantly decreased peripheral blood eosinophil and basophil counts and the frequencies of regulatory T cells (Tregs), and increased the frequencies of Th2 cells. To our knowledge, this is the first study to show benralizumab treatment increasing circulating Th2 cells and decreasing circulating Tregs. Finally, the ROC curve to discriminate patients who achieved clinical effectiveness of benralizumab treatment revealed that the frequency of circulating Th17 cells and FeNO levels might be used as parameters for predicting the real-world response of benralizumab treatment in patients with severe asthma.

Effect of Japanese Cedar Pollen Sublingual Immunotherapy on Asthma Patients with Seasonal Allergic Rhinitis Caused by Japanese Cedar Pollen.

Allergen immunotherapy is a promising treatment for allergic diseases that induce immune tolerance through the administration of specific allergens. In this study, we investigate the efficacy of sublingual immunotherapy (SLIT) in asthmatic patients with SAR-JCP and the dynamics of the parameters before and after treatment in a real-world setting. This was a prospective single-center observational study. Patients with asthma and SAR-JCP (n = 24) were recruited for this study and assessed using symptom questionnaires before SLIT and a year after the SLIT. In addition, a respiratory function test, forced oscillation technique, and blood sampling test were performed during the off-season before and after SLIT. The one-year SLIT for asthma patients with SAR-JCP significantly improved not only allergic rhinitis symptoms, but also asthma symptoms during the JCP dispersal season, and significantly improved airway resistance during the off-season. The change in the asthma control test and the visual analog scale score during the season before and after SLIT was negatively and positively correlated with the change in peripheral blood γδ T cells off-season before and after SLIT, respectively. It was suggested that improvement in asthma symptoms during the JCP dispersal season after SLIT was associated with reduced peripheral blood γδ T cells.