Involvement of Muscarinic M3 Receptor in the Development of M2 Macrophages in Allergic Inflammation.

INTRODUCTION: The muscarinic M3 receptor antagonist, tiotropium, has a bronchodilatory effect on asthma patients. Additionally, tiotropium inhibits allergic airway inflammation and remodeling in a murine asthma model. However, the underlying mechanisms of this M3 receptor antagonist remain unclear. Therefore, we investigated the effect of muscarinic M3 receptor blockage on M2 macrophage development during allergic airway inflammation. METHODS: BALB/c mice were sensitized and challenged with ovalbumin to develop a murine model of allergic airway inflammation mimicking human atopic asthma. During the challenge phase, mice were treated with or without tiotropium. Lung cells were isolated 24 h after the last treatment and gated using CD68-positive cells. Relm-α and Arginase-1 (Arg1) (M2 macrophage markers) expression was determined by flow cytometry. Mouse bone marrow mononuclear cell-derived macrophages (mBMMacs) and human peripheral blood mononuclear cells (PBMCs)-derived macrophages were stimulated with IL-4 and treated with a muscarinic M3 receptor antagonist in vitro. RESULTS: The total cells, eosinophils, and IL-5 and IL-13 levels in BAL fluids were markedly decreased in the asthma group treated with tiotropium compared to that in the untreated asthma group. The Relm-α and Arg1 expression in macrophages was reduced considerably in the asthma group treated with tiotropium compared to that in the untreated asthma group, suggesting that the development of M2 macrophages was inhibited by muscarinic M3 receptor blockage. Additionally, muscarinic M3 receptor blockage in vitro significantly inhibited M2 macrophage development in both mBMMacs- and PBMCs-derived macrophages. CONCLUSIONS: Muscarinic M3 receptor blockage inhibits M2 macrophage development and prevents allergic airway inflammation. Moreover, muscarinic M3 receptors might be involved in the differentiation of immature macrophages into M2 macrophages.

Fetal Lung Cells Transfer Improves Emphysematous Change in a Mouse Model of Neutrophil Elastase-Induced Lung Emphysema.

Recently, several studies for lung regeneration have been reported. However, regenerating the lung tissue by the transfer of any cells directly to the lung has been hardly successful. The aim of this study was to evaluate the effect of fetal lung cells (FLCs) in a mouse model of lung emphysema. C57BL/6 mice were stimulated with neutrophil elastase (NE) intra-tracheally (i.t.) to generate lung emphysema. To collect fetal lung cells, C57BL/6-Tg (CAG-EGFP) mice were bred for 14 days. Before delivery, the bred mice were euthanized, and fetal lungs were harvested from the fetal mice and the cells were collected. The FLCs were transferred i.t. 24 h after the NE instillation. Four weeks after the NE instillation, mice were euthanized, and the samples were collected. The mean linear intercept (MLI) was significantly prolonged in the NE instillation group compared to the control group. However, in the FLCs transfer group stimulated with NE, the MLI became shorter than the NE-stimulated group without an FLCs transfer. This result shows that an FLCs transfer inhibited the progression of lung emphysema. Additionally, motility of the mice was also improved by the FLCs transfer. These results indicate that transfer of the FLCs, which were presumed to be progenitor cells for lung tissue, may improve the emphysematous change.

Comprehensive Gene Expression Signature Using RNA-Seq in Airways of Mouse Model of Severe Asthma with Fungal Sensitization.

INTRODUCTION: Inhalation of fungal allergens induces airway epithelial damage following airway inflammation and excessive mucus secretion, which can lead to severe asthma with fungal sensitization (SAFS). Comprehensive gene expression analysis in Alternaria-exposed mouse airways, a model of SAFS, has not been conducted. METHODS: BALB/c mice received intranasal administration of Alternaria extract or phosphate-buffered saline twice a week for 6 weeks. Lung sections and bronchoalveolar lavage fluid were obtained to assess airway inflammation. RNA-Seq in the central airway was performed, and gene ontology (GO) analysis and gene set enrichment analysis (GSEA) were conducted for pathway analyses. An in vitro experiment using human airway epithelial cell 16HBE14o- was performed to validate the RNA-Seq findings. RESULTS: Eosinophilic airway inflammation with mucus overproduction and airway remodeling was observed in mice exposed to Alternaria. RNA-Seq analysis revealed 403 upregulated and 108 downregulated genes in airways of Alternaria-exposed mice. In GO analysis, the functions of immunoglobulin (Ig) receptor binding, Ig production, inflammatory response, and T-cell activation were upregulated, while those of keratinization and defense response to other organisms were downregulated. GSEA revealed positive enrichment in T-cell receptor complex, immunological synapse, antigen binding, mast cell activation, and Ig receptor binding, and negative enrichment in keratinization and cornification in Alternaria-exposed mice relative to control. Alternaria exposure to 16HBE14o- cells validated the downregulation of epithelial keratinization-related genes, including SPRR1A, SPRR1B, and KRT6B. CONCLUSION: RNA-Seq analysis showed that Alternaria exposure induced inflammatory response and impaired defense mechanisms in mice airway epithelium, which might be therapeutic targets for SAFS.

Downregulation of type III interferons in patients with severe COVID-19.

Coronavirus disease 2019 (COVID-19) is globally rampant, and to curb the growing burden of this disease, in-depth knowledge about its pathophysiology is needed. This was an observational study conducted at a single center to investigate serum cytokine and chemokine levels of COVID-19 patients, based on disease severity. We included 72 consecutive COVID-19 patients admitted to our hospital from March 21 to August 31, 2020. Patients were divided into Mild-Moderate I (mild) and Moderate II-Severe (severe) groups based on the COVID-19 severity classification developed by the Ministry of Health, Labor and Welfare (MHLW) of Japan. We compared the patient characteristics as well as the serum cytokine and chemokine levels on the day of admission between the two groups. Our findings indicated that the severe group had significantly higher levels of serum fibrinogen, d-dimer, lactate dehydrogenase, C-reactive protein, ferritin, Krebs von den Lungen-6, surfactant protein (SP)-D, and SP-A than the mild group. Strikingly, the levels of interleukin (IL)-28A/interferon (IFN)-λ2 were significantly lower in the severe group than in the mild group. We believe that reduced levels of type III interferons (IFN-λs) and alterations in the levels of other cytokines and chemokines may impact the severity of the disease.

Investigating Patient and Family Satisfaction with the Respiratory Status in Patients with Chronic Obstructive Pulmonary Disease.

The current chronic obstructive pulmonary disease (COPD) management aims to improve the patients' quality of life and healthy life expectancy; however, few studies have evaluated the level of satisfaction with the patients' current respiratory status in COPD patients and their families. This study aimed to examine the level of patient and family satisfaction with the patients' current respiratory status and to identify the clinical factors closely linked to dissatisfaction.This multicenter, cross-sectional study included 454 outpatients with COPD and 296 family members. Patients and families were allocated to the satisfied and dissatisfied groups based on their satisfaction with the patients' current respiratory status. Patients' health status, dyspnoea, appetite, respiratory function, and mood disorders were assessed.Among the participants of this study, 67% of patients and 60% of their families were dissatisfied with the patients' current respiratory status. The COPD assessment test (CAT) was the most sensitive marker of dissatisfaction compared to other clinical factors (p < 0.01). The statistical cut-off value of CAT for predicting patient dissatisfaction was 11. CAT reflected patient dissatisfaction independent of age, sex, dyspnoea, appetite, mood disorders, body mass index, and respiratory function (odds ratio: CAT; 1.12 (1.07-1.19): p < 0.01).Many patients and families are dissatisfied with the patients' respiratory status, and the patients' CAT score is useful to predict dissatisfaction. Our findings are consistent with the Global Initiative for Chronic Obstructive Lung Disease indicating that treatment should be enhanced in patients with a CAT score ≥10. Furthermore, treatment strategies targeting CAT may contribute to an improved patient satisfaction.

The Effect of Bronchoconstriction by Methacholine Inhalation in a Murine Model of Asthma.

INTRODUCTION: Bronchoconstriction was recently shown to cause airway remodeling and induce allergic airway inflammation in asthma. However, the mechanisms how mechanical stress via bronchoconstriction could induce airway inflammation and remodeling remain unclear. OBJECTIVE: We investigated the effect of bronchoconstriction induced by methacholine inhalation in a murine model of asthma. METHODS: BALB/c female mice were sensitized and challenged with ovalbumin (OVA), followed by treatment with methacholine by a nebulizer twice a day for 7 days. Twenty-four hours after the last methacholine treatment, the bronchoalveolar lavage fluid (BALF) and lung tissues were collected. The BALF was analyzed for total and differential cell counts and cytokine levels. The lung tissues were analyzed for goblet cell metaplasia, thickness of the smooth muscle, and lung fibrosis. The expression of cytokines in the lung was also examined. RESULTS: OVA sensitization and challenge induced infiltration of total cells, macrophages, and eosinophils in the BALF along with goblet cell metaplasia and increased airway smooth muscle hypertrophy. Seven days after the last OVA challenge, untreated mice achieved reduction in airway inflammation, while methacholine maintained the number of BALF total cells, macrophages, and eosinophils. The percentage of goblet cells and the thickness of airway smooth muscle were also maintained by methacholine. Moreover, the treatment of methacholine induced the expression of transforming growth factor (TGF)-ß in the lung. This result indicates that the production of TGF-ß is involved in induction of airway remodeling caused by bronchoconstriction with methacholine. CONCLUSIONS: Repeated bronchoconstriction caused by methacholine inhalation elicited allergic airway inflammation and airway remodeling.

Oral meal intake as a prognostic predictor of community-acquired pneumonia: A retrospective cohort study.

INTRODUCTION: The association between oral intake volume and prognosis has not been studied in hospitalized patients with community-acquired pneumonia (CAP). METHODS: We retrospectively examined 503 hospitalized CAP patients to evaluate whether early-phase meal intake (EMI) (within the first 24 h after hospitalization) and maximum meal intake (MMI) (on the day during hospitalization) are useful prognostic predictors. RESULTS: Of the 503 patients, 40 (8.0%) died within 30 days. Area under the curve (AUC) for prognosis was comparable between EMI, A-DROP, and serum albumin [EMI: 0.80, 95% confidence interval (CI) 0.75-0.84; A-DROP: 0.77, 95% CI 0.71-0.83; Serum albumin: 0.72, 95% CI 0.64-0.79]. Mortality rate was <1% in patients with EMI ≥ 50%. Univariate analysis showed that patients with EMI < 50% showed poor prognosis [odds ratio 53.4, 95% CI 7.2-392.2]. Multivariate analysis showed that EMI was an independent prognostic predictor [odds ratio 23.6, 95% CI 3.11-179.7]. AUC of MMI for prognosis was 0.94 (95% CI 0.91-0.96); mortality rate was <1% for patients who ingested ≥50% of meals on any day during hospitalization. We defined ingesting ≥50% of meals on any day during hospitalization as oral intake stability. Multivariate analyses revealed an association between oral intake stability and prognosis. Odds ratio of oral intake stability for prognosis was higher than that of conventional evaluations (vital sign and CRP level stability). Fewer days were required to reach oral intake stability than to reach vital sign and CRP level stability. CONCLUSIONS: Oral intake is a simple, non-invasive, cost-free, and powerful prognostic predictor for patients with CAP.

Exposure to intermittent hypoxia inhibits allergic airway inflammation in a murine model of asthma.

PURPOSE: Obesity increases the severity of asthma, and patients with severe asthma are often complicated with obstructive sleep apnea syndrome (OSAS), a concomitant disease of obesity. We investigated whether intermittent hypoxia (IH), which is a physiological feature of OSAS, modifies allergic airway inflammation in a murine model of asthma. METHODS: Balb/c mice were sensitized by ovalbumin (OVA) intraperitoneally twice (days 1 and 14) and challenged with intranasal OVA three times (days 21, 22, and 23). The mice were exposed to IH either from days 1 to 24 (long exposure) or only from days 21 to 24 (short exposure). The impact of IH exposure to allergic airway inflammation was investigated using these mice models by histologic, morphometric, and molecular techniques. Additionally, the airway responsiveness to acetylcholine was also assessed. RESULTS: OVA-sensitized and OVA-challenged mice exposed to room air (RA) showed increased total cell and eosinophil numbers in the BALF. The levels of interleukin (IL)-5 and IL-13 in the BALF also increased and goblet cell metaplasia was induced. In contrast, both long and short exposure to IH inhibited the increased total cell and eosinophil numbers. The levels of IL-5 and IL-13 in the BALF also decreased on exposure to IH. Moreover, the goblet cell hyperplasia and airway hyperresponsiveness were significantly reduced in mice exposed to IH compared to those exposed to RA. CONCLUSIONS: These results suggest that IH may not deteriorate the asthmatic condition in a murine model of asthma.

Inhibition of Virus-Induced Cytokine Production from Airway Epithelial Cells by the Late Addition of Budesonide.

BACKGROUND: Viral infection is the main cause of asthma and COPD (chronic obstructive pulmonary disease) exacerbation and accumulate inflammatory cells to airway tissue. We have reported poly I:C, a mimic product of the virus and ligand of toll-like receptor 3 (TLR3), induced inflammatory chemokines from airway epithelial cells and found prior incubation with corticosteroids diminishes the effect of TLR3 activation. In clinical practice, mild asthma is recommended as-needed budesonide (BUD) when symptoms occur following a viral infection, etc. However, many questions still surround BUD's usefulness if taken after a virus has already infected airway tissue. OBJECTIVE: The aim of this study was to investigate the inhibitory effects of BUD on inflammatory cytokines induced by viral infection. Methods: Normal human bronchial epithelial (NHBE) cells were stimulated with poly I:C or infected with human rhinovirus-16 (HRV16) and BUD was added after the initial stimulation. Expression of both thymic stromal lymphopoietin (TSLP) and CCL26/eotaxin-3 was quantified by real-time RT-PCR and enzyme-linked immunosorbent assay (ELISA), respectively. Knockdown study was performed. Results: Pre-or post-incubation with BUD inhibited both poly I:C- and HRV16-induced mRNAs and proteins of both thymic stromal lymphopoietin (TSLP) and CCL26 with significance. Knockdown of the glucocorticoid receptor diminished these effects of BUD. Under the same conditions of BUD's experiment, post-incubation with neither fluticasone propionate nor dexamethasone suppressed expression of both TSLP and CCL26, which induced by poly I:C. CONCLUSION: Post-addition of BUD inhibited the virus-induced TSLP and CCL26 from the airway epithelial cells. These results suggest that inhalation of BUD after viral infection has beneficial effects on asthma. CONCLUSION: Late addition of BUD may benefit among patient with viral infection and type 2 allergic airway disease such as asthma.

Beneficial Effect of Early Intervention with Garenoxacin for Bacterial Infection-Induced Acute Exacerbation of Bronchial Asthma and Chronic Obstructive Pulmonary Disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) and asthma have similar clinical features and are both exacerbated by airway infection. OBJECTIVE: To determine whether garenoxacin mesylate hydrate (GRNX) added to the standard care for bacterial infection-induced acute exacerbation of asthma or COPD in adults has clinical benefits. METHOD: This single-arm clinical trial was conducted from January 2015 to March 2016. Adults with a history of asthma or COPD for more than 12 months were recruited within 48 h of presentation with fever and acute deterioration of asthma or COPD requiring additional intervention. Participants were administered 400 mg GRNX daily for 7 days without additional systemic corticosteroids or other antibiotics. The primary outcome was efficacy of GRNX based on clinical symptoms and blood test results after 7 days of treatment. Secondary outcomes were: (1) comparison of the blood test results, radiograph findings, and bacterial culture surveillance before and after treatment; (2) effectiveness of GRNX after 3 days of administration; (3) analyzation of patient symptoms based on patient diary; and (4) continued effectiveness of GRNX on 14th day after the treatment (visit 3). RESULTS: The study included 44 febrile patients (34 asthma and 10 COPD). Frequently isolated bacteria included Moraxella catarrhalis (n = 6) and Klebsiella pneumoniae (n = 4). On visit 2, 40 patients responded, and no severe adverse events were observed. All secondary outcomes showed favorable results. CONCLUSION: GRNX effectively treated asthma and COPD patients with acute bacterial infection without severe adverse events. Further research with a larger study population is needed.

Antibody therapy for the management of severe asthma with eosinophilic inflammation.

One of the characteristic features of asthma is chronic airway inflammation typically with eosinophil infiltration. Most asthmatics can be treated successfully with conventional treatment appropriate for their severity, but in some severe cases, asthma cannot be well controlled even with thorough treatment and this condition is known as 'refractory asthma'. To overcome severe refractory asthma, a new therapeutic strategy with biologics has been developed based on the knowledge of molecular mechanisms of airway inflammation in asthma, induced by the condition of high Th2-type responses and activation of eosinophils as well as allergic reactions. Humanized anti-human IgE antibody (anti-IgE; omalizumab) was the first biological preparation approved for treating asthma. Based on clinical evidence, treatment with anti-IgE (anti-IgE therapy) has been accepted as a new therapeutic approach for severe allergic asthma in adults since 2009 and in children since 2012 and has been shown to have ~60% efficacy. More recently, a humanized anti-IL-5 antibody (anti-IL-5; mepolizumab) was launched in June 2016 and has attracted great interest due to its potential effects. Several clinical studies are also ongoing to evaluate the biological preparations targeting IL-5 receptor α (IL-5Rα), IL-4 receptor α (IL-4Rα), which is shared by IL-4 and IL-13, thymic stromal lymphopoietin (TSLP) and IL-33. The new strategy with biologics targeting eosinophilic airway inflammation might open a new array for us to overcome severe refractory asthma in the future.

Cardiac and respiratory effects of deep regional hyperthermia using an 8 MHz radiofrequency-capacitive device on patients with cancer.

PURPOSE: Hyperthermia (HT), an adjuvant therapy for variable cancers, may cause physiological changes in the patients, which may lead to cardiovascular problems. Among various HT treatments, the physiological effects of deep regional HT are still unclear. We examined the physiological alterations throughout deep regional HT to improve the HT safety. MATERIALS AND METHODS: Thirty-one patients (age: 61 ± 12 years) with cancer received HT in the thoracic or upper abdominal regions using an 8-MHz radiofrequency-capacitive-device for 50 min. Rectal temperature (Trec), systolic and diastolic blood pressures (SBP and DBP), pulse rate (PR), respiratory rate (RR), percutaneous oxygen saturation (SpO2) and sweating volume were evaluated throughout HT. RESULTS: At 50 min after starting HT, Trec, PR and RR were significantly increased compared with the baseline values (Trec: 38.2 ± 1.4 vs. 36.3 ± 0.8 °C, p < 0.001, PR: 104 ± 15 vs. 85 ± 16 bpm, p < 0.05, RR: 23 ± 3 vs. 21 ± 3/min, p < 0.05). Although the average SBP and DBP were both stable during HT in a recumbent position, these values dropped significantly in a standing position (SBP: 113 ± 16 vs. 127 ± 18 mmHg, p < 0.001, DBP: 70 ± 12 vs. 75 ± 13 mmHg, p < 0.01). The total amount of sweating was 356 ± 173 g/m2 on average. CONCLUSIONS: Deep regional HT increased the deep body temperature and resulted in an increase of sweating with peripheral vasodilatation. Consequently, a significant reduction in BP would be induced on standing after HT. Careful attention is needed for patients receiving HT, especially when standing after HT.

Predicting future risk of exacerbations in Japanese patients with adult asthma: A prospective 1-year follow up study.

BACKGROUND: To avoid future risk is a definitive goal of long-term asthma management. Exacerbations are considered to be the most relevant future risk in real life asthma management. Few comparative studies have evaluated the risk factors associated with exacerbations in Japanese patients with asthma. METHODS: We performed the prospective 1-year follow up study in Japanese patients with adult asthma. A total of 189 patients with asthma were enrolled and followed up for 1 year. Finally, 181 patients completed the study protocol. RESULTS: Of 181 patients, 43 patients (23.8%) had exacerbations during the follow-up period. Among the 45 patients who had exacerbations during the preceding year, 32 patients (71.1%) had exacerbations. Prevalence of patients with previous exacerbations and those with previous admissions were significantly higher in patients with exacerbations than those with no exacerbation. Logistic regression analysis also identified a significant association between exacerbations during the follow-up period and exacerbations during the preceding year, admissions during the preceding 3 years, ACT score below 20, low %FVC (<80%), or low FEV1 (<70%), respectively. Of the 55 patients with severe asthma, 29 patients (52.7%) had exacerbations. Among the 36 patients with severe asthma with previous exacerbations, 26 patients (72.2%) had exacerbations. The history of exacerbations during the preceding year was associated with a significantly increased risk of exacerbations both among the patients with severe asthma and those with non-severe asthma. CONCLUSIONS: This study implicated that exacerbations during the preceding year reliably predict future risk of exacerbations in Japanese patients with asthma.

Evaluation of the association between sensitization to common inhalant fungi and poor asthma control.

BACKGROUND: Fungi are well-known airborne allergens that are predisposing environmental factors to asthma. Few comparative studies have evaluated sensitization to common inhalant fungi in relation to poor asthma control in patients with asthma. OBJECTIVE: To evaluate the association between sensitization to individual fungi and asthma control and elucidate the characteristics of patients with poorly controlled asthma sensitized to fungi. METHODS: This cross-sectional study was performed at Showa University Hospital between September 2014 and December 2014. The specific IgE levels for several major aeroallergens, including house dust mites, Japanese cedar, various types of pollen, furry animals, or insects, were measured with a fluorescent enzyme immunoassay in 160 patients with adult asthma. RESULTS: Fungal sensitization was predominant in men with asthma, and it was associated with poor asthma control. Sensitization to house dust mites, Japanese cedar, pollen, furry animals, or insects was not associated with poor asthma control. Logistic regression analyses revealed that patients sensitized to Aspergillus and Penicillium had a significantly increased risk of poor asthma control. More Penicillium IgE-positive patients were men and pet owners compared with Penicillium IgE-negative patients; in addition, Penicillium IgE-positive patients had higher total IgE levels. The Asthma Control Test level was significantly higher in Penicillium IgE-positive patients than in Penicillium IgE-negative patients. However, there were no differences in fractional exhaled nitric oxide, forced vital capacity, and forced expiratory volume in 1 second. Finally, sensitization to Aspergillus, Cladosporium, and Trichophyton were positively correlated with sensitization to Penicillium. CONCLUSION: Sensitization to fungi is predominant in men, and it is associated with poor asthma control. In particular, sensitization to Penicillium and Aspergillus is a risk factor for asthma severity. These results have potential relevance in asthma management.

[The Safety and efficacy of airway-hyperresponsiveness test for asthma using by SK-1211 (Methacholine Chloride)].

BACKGROUND: In abroad, Methacholine Chloride (Provocholine®) is used to meet the indications of the diagnosis of bronchial airway hyperreactivity in subjects who do not have clinically apparent asthma. We examined efficacy, safety and pharmacokinetics of Methacholine Chloride (name of study drug: SK-1211) in order to get approved for the airway hyperresponsiveness test in Japan. METHODS: Fifteen adult healthy volunteers, fifteen adult patients with asthma and ten pediatric patients with asthma were enrolled in this study. The airway hyperresponsiveness test with SK-1211 was conducted in accordance with Japanese Society of Allergology Standard Method. RESULTS: When the threshold value of PC20 was 8 mg/mL, the sensitivity of adult patients with asthma was 66.7% (10/15 subjects) and the specificity of adult healthy volunteers was 86.7% (13/15 subjects). The sensitivity of pediatric patients with asthma was 70.0% (7/10 subjects). Not all subjects experienced some adverse reactions during inhalation of SK-1211, all of which were mild in severity and resolved soon with inhalation of a bronchodilator. There were no serious adverse reactions reported. CONCLUSION: The airway hyperresponsiveness test with SK-1211 was no specific concern with safety and useful in the diagnosis of bronchial airway hyperresponsiveness.

Influence of Omalizumab on Allergen-Specific IgE in Patients with Adult Asthma.

BACKGROUND: Omalizumab, an anti-immunoglobulin E (IgE) monoclonal antibody, inhibits the binding of circulating IgE to mast cells and basophils, resulting in fewer episodes of airway inflammation, asthma symptoms and exacerbations in patients with severe allergic asthma. Treatment of patients with asthma using omalizumab increases serum total IgE (tIgE) levels. However, little is known about the influence of omalizumab on allergen-specific IgE (sIgE). METHODS: tIgE and sIgE in 47 adult patients with severe asthma were measured with a fluorescent enzyme immunoassay (ImmunoCAP-FEIA) before and after omalizumab treatment. RESULTS: Treatment with omalizumab increased tIgE and sIgE levels. The increases in sIgE by class category after omalizumab treatment were positively correlated with baseline sIgE positivity before treatment. The mean changes in sIgE levels after omalizumab treatment were also correlated with baseline sIgE levels before treatment. The mean changes in tIgE levels were positively correlated with the mean changes in IgE levels against Dermatophagoides pteronyssinus, crude house dust, Japanese cedar and moth. Omalizumab markedly influenced the negative-to-positive seroconversion rate for IgE against Japanese cedar (30.8%), Candida (29.0%) and moth (28.0%). Finally, all patients with negative-to-positive seroconversion for Japanese cedar-specific IgE had cedar pollinosis before beginning omalizumab treatment. CONCLUSIONS: The changes in sIgE levels after omalizumab treatment may be dependent on the baseline sIgE levels. Our data may indicate the presence of undetectable but functional sIgE.

Association between specific IgE to Staphylococcus aureus enterotoxins A and B and asthma control.

BACKGROUND: Recent studies have found that serum levels of Staphylococcus aureus enterotoxin (SE)-IgE are higher in patients with severe asthma compared with patients with nonsevere asthma. However, the association between SE-IgE and asthma control is not fully understood. Furthermore, SEA and SEB were the first reported SEs and subdivided into different groups. The influences of SEA-IgE and SEB-IgE on asthma control have not been elucidated. OBJECTIVE: To determine the relevance of SEA- and SEB-IgE in patients with adult asthma and to investigate the association of SEA-IgE, SEB-IgE, and asthma control, respectively. METHODS: The serum concentrations of SEA- and SEB-IgE in 172 adults with asthma were measured with a fluorescent enzyme immunoassay. RESULTS: The prevalence of SEA- and SEB-IgE was 16.2% and 22.1%, respectively. Total IgE levels and the prevalence of atopic dermatitis were higher in SEA-IgE- and SEB-IgE-positive patients than in SEA-IgE- and SEB-IgE-negative patients, respectively; more SEA-IgE- and SEB-IgE-positive patients owned pets. Sensitization to SEA was associated with a younger mean age and a younger mean age at asthma onset. Multiple regression analysis indicated an association between total IgE levels and SEB-IgE. The prevalence of poorly uncontrolled asthma was significantly higher in SEA-IgE-positive patients than in SEA-IgE-negative patients. In addition, fractional exhaled nitric oxide levels were higher in SEA-IgE-positive patients than in SEA-IgE-negative patients. Logistic regression analysis also identified an association between SEA-IgE and poor asthma control. CONCLUSION: Our findings indicate that sensitization to SE, in particular SEA rather than SEB, is associated with poor asthma control in adults with asthma.

Group V secretory phospholipase A2 is involved in macrophage activation and is sufficient for macrophage effector functions in allergic pulmonary inflammation.

We reported that Pla2g5-null mice lacking group V secretory phospholipase A2 (gV-sPLA2) showed reduced eosinophilic pulmonary inflammation and Th2 cytokine generation when challenged with an extract from house dust mite Dermatophagoides farinae, compared with wild-type (WT) controls. Adoptive transfer studies suggested that gV-sPLA2 in dendritic cells was necessary for sensitization of Pla2g5-null mice, but was not sufficient to induce the effector phase of pulmonary inflammation. In this study, we demonstrate that gV-sPLA2 is inducibly expressed in mouse and human macrophages (M) activated by IL-4 and is required for the acquisition of M effector functions that facilitate the effector phase of pulmonary inflammation. We demonstrate that gV-sPLA2 expression in M is sufficient for the development of pulmonary inflammation, even when inflammation is induced by intrapulmonary administration of IL-4. The concentrations of CCL22/CCL17 and effector T cell recruitment are severely impaired in Pla2g5-null mice. Intratracheal transfers of enriched CD68(+) cells isolated from the lungs of D. farinae-challenged WT donor mice induce eosinophilia, chemokine production, and recruitment of T cells into the lungs of Pla2g5-null recipients previously sensitized by WT D. farinae-loaded dendritic cells. Our studies identified a unique function of gV-sPLA2 in activation of M and in their capacity to recruit T cells to amplify the effector phase of pulmonary inflammation.