Changes in disease burden and treatment reality in patients with severe asthma.

BACKGROUND: Biologics are clinically available for patients with severe asthma, but changes in asthma control over time are unknown. We examined changes in disease burden and treatment in severe asthma patients. METHODS: This retrospective study used a Japanese health insurance database (Cross Fact) and included patients aged ≥16 years treated continuously with an inhaled corticosteroid (ICS) for a diagnosis of asthma in each calendar year from 2015 to 2019. Severe asthma was defined as annual use of high-dose ICS plus one or more asthma controller medications four or more times, oral corticosteroids for ≥183 days, or biologics for ≥16 weeks. Changes in asthma exacerbations, prescriptions, and laboratory testing were examined. RESULTS: Demographic characteristics were similar throughout the study. The number and proportion of patients with severe asthma among those with asthma increased (2724; 15.3% in 2015 vs 4485; 19.0% in 2019). The proportion of severe asthma patients with two or more asthma exacerbations decreased from 24.4% to 21.5%. Odds ratios (95% confidence interval) of ≥2 asthma exacerbations in each year compared with 2015 were 0.96 (0.85-1.08) in 2016 and 0.86 (0.76-0.97) in 2017, with significant reductions observed in subsequent years. Short-acting beta agonists and oral corticosteroid prescriptions for asthma exacerbations decreased and long-acting muscarinic antagonist and biologic prescriptions for maintenance treatment increased. CONCLUSIONS: This study showed improvements in disease burden and treatment in severe asthma patients. There remains an unmet medical need for patients with severe asthma, given the proportion who continue to have asthma exacerbations.

[Mechanism of action of tezepelumab (TEZSPIRE®) and clinical trial results in |asthma].

Tezepelumab (TEZSPIRE® Subcutaneous Injection 210 |mg), a biologic medicine with a novel mechanism, was approved in Japan in September 2022 for the treatment of bronchial asthma. Tezespire auto-injector was approved in Japan in August 2023 as an additional dosage. It is indicated for severe or refractory patients whose asthmatic symptoms cannot be controlled by currently available treatment. Tezepelumab binds to the epithelial cytokine thymic stromal lymphopoietin (TSLP) and disrupts TSLP signaling via the heterodimeric receptor. In the Phase 3 NAVIGATOR trial, the annual asthma exacerbation rate was significantly reduced by tezepelumab when administered subcutaneously every 4 weeks over a 52-week period to patients with uncontrolled, severe asthma who had received medium- or high-dose inhaled glucocorticoids. Its efficacy in reducing asthma exacerbations was observed regardless of blood eosinophil (bEOS) count, fractional exhaled nitric oxide (FeNO) levels, or serum total IgE at baseline. Significant improvements were noted in lung function, health-related quality of life, and change from baseline in asthma control. Reductions in the levels of inflammatory biomarkers (bEOS, FeNO, and IgE) was also noted. Clinical pharmacology trials demonstrated the efficacy of tezepelumab in improving airway hyperresponsiveness. In this article, we reviewed pharmacological characteristics, pharmacokinetics, clinical efficacy, and the safety profile of tezepelumab.

A Retrospective Claims Database Study to Clarify Treatment Reality of Asthma Patients Before and After Referral to a Specialist.

Purpose: Japanese guidelines recommend that patients with uncontrolled asthma be referred by non-specialists to specialists (allergists and/or pulmonologists). This study investigated the reality of clinical practice in asthma patients referred to specialists in Japan. Patients and Methods: This was a retrospective, observational cohort study of asthma patients in a health insurance claim database (Cross Fact) referred from facilities with non-specialists to those with specialists from January 2016 to December 2018. The referred asthma patients were defined as patients with ≥4 inhaled corticosteroid (ICS)-containing prescriptions during a 1-year baseline period, with an asthma diagnosis, and who had visited a facility with specialists. Asthma exacerbation, maintenance treatment, laboratory tests, and medical procedures before and after referral were analyzed. Results: Data for 2135 patients were extracted, of which 420 with referral codes were analyzed. The proportion of patients with asthma exacerbations was 50.2% (95% confidence interval [CI]: 45.4-55.1%) before referral and 37.4% (95% CI: 32.7-42.2%) after, a significant decrease (P<0.001; McNemar test). The proportions of patients prescribed ICS alone, long-acting beta-agonists (LABA), and ICS/LABA were lower after referral than before, but the proportions of patients prescribed long-acting muscarinic antagonists (LAMA), ICS/LABA/LAMA, and biologics increased after referral. More asthma-related laboratory tests were performed after referral, and spirometry incidence increased from 16.4% before referral to 51.4% after referral. Conclusion: This study shows a decrease in asthma exacerbations, change in asthma treatments, and increase in laboratory tests after referral to a specialist, suggesting that referrals to specialists lead to better management of asthma.

Exacerbation rates in Japanese patients with obstructive lung disease: A subanalysis of the prospective, observational NOVELTY study.

BACKGROUND: Although clinical trials including asthma and COPD patients have revealed much about exacerbation frequencies, most studies are limited in that they recruited patients only with a clear diagnosis of one disease or the other, based on conventional diagnostic criteria, which may exclude many real-world patients with mixed symptoms. METHODS: NOVELTY is a global prospective observational study of patients with asthma and/or COPD from real-world practice. In this subanalysis, we compared patient characteristics of obstructive pulmonary diseases between the Japanese population (n = 820) and the overall population excluding Japanese patients (n = 10,406). RESULTS: The Japanese population had fewer exacerbations than the overall population across most of the physician-assessed disease severities and all diagnoses. The difference in exacerbation frequencies was more prominent in patients with COPD and asthma + COPD. The Japanese population was older, had higher former smoking rates, lower BMI, fewer respiratory symptoms, and better health-related quality of life compared with the overall population across all diagnoses. CONCLUSIONS: We clarified differences in patient characteristics among patients with asthma and/or COPD in Japan compared with non-Japanese patients. Importantly, we found that Japanese patients with asthma and/or COPD had significantly fewer exacerbations compared with patients overall. The results from our study may contribute to the development of precision medicine and guidelines specific to Japan.

Oral Corticosteroid Reduction Between Biologics Initiated and Non-Initiated Patients with Severe Asthma.

Purpose: The oral corticosteroid (OCS)-sparing effect of several biologics (BIOs) has been shown in clinical trials. To date, no study has evaluated differences in OCS dose reduction between BIO-initiated and BIO-non-initiated patients in real-world clinical practice. We compared dose reductions in maintenance OCS between BIO-initiated and BIO-non-initiated severe asthma patients in a real-world setting. Patients and Methods: This retrospective cohort study used the data from the Diagnosis Procedure Combination database of Medical Data Vision in Japan. Severe asthma patients with continuous use of OCS were selected from December 2015 to February 2020. The primary endpoint was the proportion reduction in daily maintenance OCS dose from Week 0 to Week 24. Analyses were performed using inverse probability treatment weighting. Results: In total, 2927 patients were included (BIO-initiated: 239 patients, BIO-non-initiated: 2688 patients). Adjusted median (quartile [Q] 1-Q3) proportion reduction in daily maintenance OCS dose at Week 24 from the index date was 25.0% (0.0-100.0%) and 0.0% (0.0-83.3%) in the BIO-initiated and BIO-non-initiated groups, respectively (Hodges-Lehmann estimate [95% confidence interval], 0.0000% [0.0000-0.3365%]). Respective proportions of patients in the BIO-initiated and BIO-non-initiated groups achieving dose reductions from the index date in the daily maintenance OCS dose at Week 24 were >0% reduction, 56.6% and 44.1% (odds ratio [OR] 1.6554); ≥25% reduction, 50.5% and 40.6% (OR 1.4888); ≥50% reduction, 42.8% and 33.7% (OR 1.4714); and 100% reduction, 26.2% and 24.4% (OR 1.1005). Conclusion: Among severe asthma patients, the daily dose of maintenance OCS was reduced with BIO treatment. Although a higher percentage of patients in the BIO-initiated group had an OCS reduction of ≤75% than the BIO-non-initiated group, we found no clear difference in OCS reduction. Our findings will be justified by further research that incorporates a longer observation period and variables excluded from this study. Trial Registration: ClinicalTrials.gov (NCT05136547).

Characterization of Severe Uncontrolled Asthma in Japan: Analysis of Baseline Data from the PROSPECT Study.

Purpose: Treatment patterns and patient characteristics are not well elucidated among Japanese patients with severe uncontrolled asthma who currently have various treatment options, including biologics. We analyzed baseline characteristics of patients who did/did not initiate biologic treatment in PROSPECT, a 24-month observational study. Patients and Methods: Patients with severe uncontrolled asthma were prospectively enrolled at 34 sites in Japan from December 2019 to September 2021. The enrolled population was divided based on initiation/non-initiation of biologic treatment within 12 weeks after enrollment. Patient demographics, clinical characteristics, biomarker levels, and asthma-related treatment were assessed at enrollment. Results: Of 289 patients meeting the enrollment criteria, 127 patients initiated biologic treatment (BIO group: omalizumab, n = 16; mepolizumab, n = 10; benralizumab, n = 41; and dupilumab, n = 60) and 162 patients did not (non-BIO group). The proportion of patients with ≥2 asthma exacerbations was higher in the BIO group than the non-BIO group (65.0% vs 47.5%). Patients receiving omalizumab had the highest frequency of allergic rhinitis (87.5% vs other BIOs: 40.0%-53.3%). Patients receiving benralizumab and dupilumab had the highest incidence of nasal polyps (benralizumab: 19.5%, dupilumab: 23.3%, other BIOs: 0.0%). The proportion of patients with blood eosinophils ≥300 cells/µL was higher with benralizumab (75.6%) than other BIOs (26.7%-42.9%). Conclusion: This analysis of baseline data from the PROSPECT study is the first to clarify the characteristics of Japanese patients with severe uncontrolled asthma. BIOs were not necessarily prescribed to patients in whom they were indicated; however, for patients who received them, selection appeared to be made appropriately based on asthma phenotypes.

History of Respiratory Events Prior to a First COPD Diagnosis and Future Exacerbations: A Longitudinal Observational Cohort Database Study in Japan.

Background: Little is known about the association between respiratory events prior to diagnosis of chronic obstructive pulmonary disease (COPD) and future clinical outcomes in Japan. We investigated the association between pre-COPD diagnosis respiratory events and the incidence of exacerbations in a cohort of newly diagnosed COPD patients in Japan. Patients and Methods: Data were retrieved from the JMDC claims database. Patients ≥40 years old with a first COPD diagnosis (≥1 hospitalization or ≥2 outpatient claims for COPD) between 2010 and 2016 were included. The incidence rate (IR) of exacerbations in patients with or without any respiratory event (including lower respiratory tract infection and respiratory failure) in the year preceding diagnosis was compared. A negative binomial model explored the association between pre-diagnosis respiratory event and IR ratio (IRR) of exacerbations. Results: A total of 20,212 patients newly diagnosed with COPD were identified: 61% male, mean age 55 years (SD 9); of these, 955 (4.7%) had experienced ≥1 respiratory event in the year preceding diagnosis. Median duration of follow-up was 3.3 years during which the IR of exacerbations was 0.31 per patient-year (95% confidence interval [CI] 0.29-0.33) in patients with respiratory event, and 0.11 (95% CI 0.10-0.13) in patients without. The IR for severe exacerbation was nearly 10 times greater in patients with respiratory event versus without. Experiencing respiratory event pre-diagnosis was independently associated with an increased IRR of future moderate-to-severe exacerbation (adjusted IRR, 2.7; 95% CI 2.3-3.1). Conclusion: Patients experiencing respiratory events in the year preceding COPD diagnosis should be considered at-risk of worse clinical COPD outcomes.

A Retrospective Claims Database Study to Clarify Disease Burden of Severe Asthma Patients with Type 2 High or Low Inflammation.

Purpose: The disease burden of severe asthma patients stratified by type 2 (T2) biomarkers is not well studied in large patient samples, especially for T2-low severe asthma patients. Using a Japanese medical record database, we investigated disease and economic burdens in T2-high and T2-low severe asthma patients. Patients and Methods: Data of severe asthma patients (receiving high-dose inhaled corticosteroids and additional asthma-related controller medications or oral corticosteroids [OCS] prescription [≥183 days] during the 1-year baseline period) were analyzed in the Real World Data database, comprising electronic medical records from Japanese medical institutions. Severe asthma patients were stratified into a T2-high population with higher eosinophils (≥150 cells/µL) and/or higher total immunoglobulin E (IgE, ≥75 IU/mL) or a T2-low population with lower eosinophils (<150 cells/µL) and lower total IgE (<75 IU/mL). The incidence of asthma exacerbation events and drug costs were analyzed for each population. Different T2 thresholds were explored, including eosinophil count 300 cells/µL and/or IgE 150 IU/mL. Results: Of the 732 severe asthma patients, 599 (81.8%) patients had T2-high type, and 133 (18.2%) had T2-low type. Proportions of the T2-high patients (30.6%) with asthma exacerbations, defined as a composite outcome, including OCS burst, injectable steroid use, and hospitalization, were similar to those of T2-low type (34.6%). The annual drug cost was similar between T2-high (175,487 JPY) and T2-low (165,322 JPY) populations. Conclusion: In this large-scale study, both T2-high and T2-low severe asthma patients in Japan were shown to have a high disease burden and high economic burden, suggesting an unmet treatment need.

Real-World Evidence on the Diagnostic and Clinical Characteristics of Asthma in Japanese Patients with COPD: The ACO Japan Cohort Study.

Introduction: The ACO Japan Cohort Study, a multicenter observational study, investigated the proportion of patients with chronic obstructive pulmonary disease (COPD) who met the Japanese Respiratory Society (JRS) asthma-COPD overlap (ACO) diagnostic criteria, characteristics of ACO and non-ACO patients, and the patient transitions between ACO/non-ACO diagnosis over 2 years. Patients and Methods: Patients with COPD were consecutively enrolled between June and December 2018 and followed up continuously for 2 years. All participating study sites were medical institutions where respiratory specialists routinely conducted medical examinations/tests required for ACO diagnosis. Results: Among 708 patients with COPD, 101 (14.3%), 118 (16.7%), and 125 (17.7%) were diagnosed with ACO at registration, 1 year, and 2 years, respectively. In total, 22.6% of patients lacked the data necessary for ACO diagnosis throughout the 2 years. Among patients who had the necessary data for ACO diagnosis, 24.7% were diagnosed with ACO at 2 years. More ACO patients had moderate or severe exacerbations in the past year than non-ACO patients at registration (15.8% vs 6.3%, p = 0.049) and 1 year (19.4% vs 7.6%, p = 0.025). ACO patients had a greater decrease in mean forced expiratory volume in one second over 2 years than non-ACO patients (-92.0 vs 43.4 mL). Among patients diagnosed with ACO at registration, 21.4% transitioned to non-ACO after 1 year. Conversely, almost all non-ACO patients at registration remained non-ACO after 1 year. Conclusion: COPD patients with ACO determined by the JRS criteria had a high risk of exacerbations and a rapid decline in respiratory function, indicating that the JRS criteria for ACO are useful for identifying high-risk COPD patients. Testing necessary for ACO diagnosis is insufficiently performed even in real-world clinical practice of COPD specialists.

Effect of timing of bronchodilator therapy initiation on exacerbations in patients with chronic obstructive pulmonary disease: a retrospective cohort study.

BACKGROUND: The benefit of prompt vs delayed treatment initiation with inhaled long-acting bronchodilators in reducing exacerbations in chronic obstructive pulmonary disease (COPD) is unclear. This study aimed to investigate if long-acting bronchodilator therapy initiation within 30 days of COPD diagnosis reduces exacerbation risk in patients with COPD. METHODS: This was a retrospective cohort study of patients with COPD based on claims and electronic medical records data extracted from the Real World Data database. The index date (day 0) was the date of the first confirmed inpatient or outpatient COPD diagnosis between January 1, 2005, and December 31, 2018. Patients with COPD without an asthma diagnosis and aged ≥ 40 years at the index date were included. Patients who initiated inhaled long-acting bronchodilator therapy within the first 30 days (day 0 to day 29) were categorized into the "prompt therapy" group and the rest into the "delayed therapy" group. Time from day 30 post-diagnosis to the first exacerbation and annual exacerbation rate (AER) were evaluated for the overall population and those stratified by COPD phenotype, including chronic bronchitis (CB) and emphysema. RESULTS: Compared with the delayed therapy group (n = 1516), time to first exacerbation was prolonged (hazard ratio 0.78; 95% confidence interval [CI] [0.70, 0.87]) and annual rates of moderate or severe exacerbations were lower (rate ratio 0.74; 95% CI [0.65, 0.84]) in the prompt therapy group (n = 1466). Similarly, time to first exacerbation was prolonged and AERs were lower in the prompt therapy group in the subgroups of patients with CB or emphysema. CONCLUSIONS: This is the first study to demonstrate a prolonged time to first exacerbation upon initiation of long-acting bronchodilators within 30 days of COPD diagnosis. A beneficial effect was also observed in patients with CB and emphysema. Our data support advising patients to initiate long-acting bronchodilators soon after COPD diagnosis.

Real-World Status of Medical Care and Treatment of Chronic Obstructive Pulmonary Disease by Respiratory Specialists in Japan.

INTRODUCTION: The ACO Registry Study was a multicenter, prospective, observational cohort study aiming to clarify the situation of asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) within the COPD population using the Japanese Respiratory Society (JRS) criteria. We reported the proportion of patients who met the ACO criteria among the COPD population at study registration. METHODS: Using data collected at registration, we investigated the implementation of each diagnostic examination/test required for ACO diagnosis in the full analysis set. Among patients with data necessary for ACO diagnosis, ACO/non-ACO patients with/without asthma diagnosed by a physician and proportions of inhaled corticosteroid (ICS) treatments for COPD were calculated. RESULTS: Of 708 patients analyzed, 396 (55.9%) had the data necessary for ACO diagnosis, and 312 (44.1%) did not. The proportions of patients who underwent laboratory and respiratory function tests (peripheral blood eosinophil count [79.8%], fractional exhaled nitric oxide [63.7%], airway reversibility [46.8%], and total immunoglobulin [Ig] E/specific IgE [33.3%]) were lower than those who underwent subjective examinations (perennial allergic rhinitis [100%], asthma before age 40 years [97.2%], and variable/paroxysmal respiratory symptoms [94.5%]). Among patients with the data necessary for ACO diagnosis and without asthma complications according to the physician's diagnosis, 15.1% (33/219) met the ACO criteria. Of patients who met the ACO criteria, 74.3% (75/101) received ICS, and 25.7% (26/101) did not. By comparison, among patients who did not meet the ACO criteria, 35.6% (105/295) were receiving ICS, and 64.4% (190/295) were not. CONCLUSIONS: The proportion of objective laboratory and physiological tests was lower than expected, despite study sites having the clinical resources for objective tests. Most ACO patients were being treated with ICS as recommended in the JRS treatment guidelines. Attempts should be made to further increase the proper use of ICS among these patients in Japan. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03577795.

Regional differences in the incidence of asthma exacerbations in Japan: A heat map analysis of healthcare insurance claims data.

BACKGROUND: In Japan, regional differences in asthma mortality have been reported; however, regional differences in asthma exacerbations have not been studied extensively. Therefore, using a health insurance claims database, we investigated the regional differences in the incidence of asthma exacerbations in Japan. METHODS: This study used data from Medi-Scope (Japan Medical Information Research Institute Inc., Japan)-a nationwide health insurance claims database. Patients with asthma at the index date (the latest date of an asthma-related prescription with an asthma diagnosis before October 1, 2018) were included in the analysis. The pre-index period was defined as 1 year before the index date, and the follow-up period as 1 year after the index date. The incidence of asthma exacerbation events was analyzed for each region. RESULTS: The primary analysis population comprised 24,883 patients who were continuously prescribed ICS or ICS/LABA at least four times during the pre-index period. The incidence rate of asthma exacerbations with hospitalization was the highest in Chugoku (2.95/100 person-years [95% CI, 1.97-4.43]) and the lowest in Kanto (1.52/100 person-years [95% CI, 1.26-1.83]). The incidence rate of asthma exacerbations for the composite outcome of hospitalization, injectable corticosteroid prescription, and oral corticosteroid burst was the highest in Fukui (105.00/100 person-years [95% CI, 64.53-170.85]) and the lowest in Nagasaki (15.69/100 person-years [95% CI, 10.84-22.72]). CONCLUSIONS: Regional differences in the incidence of asthma exacerbations as well as their treatments were observed in Japan.

Genome-wide siRNA screening in mouse bone marrow-derived macrophages revealed that knockdown of ribosomal proteins suppresses IL-10 and enhances TNF-α production.

Macrophages play a central role in the immune response, and their diverse functions are attributed to the spectrum of their functional states. To elucidate molecules involved in modulating the balance between the anti-inflammatory cytokine IL-10 and the pro-inflammatory cytokine TNF-α, we conducted genome-wide siRNA screening. First, we established an siRNA screening system using mouse bone marrow-derived macrophages, which are a suitable model for studying functional states of macrophages in vitro. In the primary screen and the subsequent reproducibility assay, 112 siRNA pools demonstrated enhancement of IL-10 production and 497 siRNA pools suppressed IL-10 production. After a deconvolution assay for IL-10-up-regulating siRNA pools, 8 genes were identified as IL-10 repressors, including Cnot1 and Rc3h1, components of the CCR4-NOT complex known to degrade cytokine mRNAs. On the other hand, siRNA pools targeting ribosomal proteins were frequently found among those that down-regulated IL-10 production and up-regulated TNF-α production. Four pools were assayed using deconvoluted siRNAs and identified as high-confidence hits. Thus, we found that the genome-wide knockdown of 19 ribosomal proteins resulted in decreased IL-10 and increased TNF-α production.

Dichloroacetate induces regulatory T-cell differentiation and suppresses Th17-cell differentiation by pyruvate dehydrogenase kinase-independent mechanism.

OBJECTIVES: Recently, there has been a growing interest in the mechanism of action of dichloroacetate (DCA) for T-cell differentiation; however, this mechanism has not been elucidated in detail. Therefore, this study aimed to investigate the mechanism of action of DCA for Treg and Th17 differentiation with pyruvate dehydrogenase kinase (PDHK) inhibitor (AZD7545) and PDHK knockdown. METHODS: Inhibitory activity of DCA and AZD7545 against recombinant PDHK and intracellular PDH phosphorylation was measured. The effects of DCA and AZD7545 on T-cell differentiation were assessed by analysing Foxp3+ T-cell populations for Treg differentiation and IL-17A production for Th17 differentiation. For reactive oxygen species (ROS) production, DCFDA was used as an indicator. KEY FINDINGS: Dichloroacetate and AZD7545 inhibited PDHK activity of recombinant PDHK and intracellular PDH phosphorylation. DCA was capable of inducing Treg differentiation and suppressing Th17 differentiation. The effects of DCA were independent of PDHK because neither AZD7545 nor knockdown of PDHK1 or PDHK3 affected T-cell differentiation. DCA was determined to be capable of inducing ROS production, and the effects of DCA on T-cell differentiation were shown to be dependent on ROS production. CONCLUSIONS: Dichloroacetate possesses Treg induction and Th17 suppression, which is independent of PDHK and dependent on ROS production.

Guanylate-binding protein 5 is a marker of interferon-γ-induced classically activated macrophages.

Macrophage activation is the main immunological process occurring during the development of several diseases, and the heterogeneity of macrophage activation or differentiation has been suggested to be involved in disease progression. In the present study, we attempted to identify molecules specifically expressed on human classically activated macrophages (M1) to investigate the significance of the M1-like phenotype in human diseases. Human monocyte-derived macrophages were differentiated into M1, M2a, M2b and M2c phenotypes, and also M1(-) (the M1 phenotype differentiated with interferon-γ) to eliminate the strong effects of lipopolysaccharides (LPS) on the gene expression profile. The gene expression profiles of those macrophage phenotypes were analyzed by a cDNA microarray analysis and were used for a bioinformatics examination to identify the markers of the M1 phenotype that are expressed in both M1 and M1(-). The gene expression profiles of murine macrophages were also evaluated. We identified guanylate-binding protein 5 (GBP5), which is associated nucleotide-binding domain and leucine-rich repeat containing gene family, pyrin domain containing 3 (NLRP3)-mediated inflammasome assembly in the M1 macrophages of both humans and mice. Notably, the expression of GBP5 protein was detected in cultured M1(-) as well as in M1 macrophages by western blotting, which means that GBP5 is a more generalized marker of the M1 phenotype compared with the M1 markers that can be induced by LPS stimulation. GBP5 is a useful candidate marker of the M1 phenotype.

Quantitative analysis of cadherin-11 and ß-catenin signalling during proliferation of rheumatoid arthritis-derived synovial fibroblast cells.

OBJECTIVES: Cadherin-11 (CDH11) is an adhesion molecule that anchors ß-catenin and is involved with various functions of synovial fibroblast cells (SFCs) during the development of rheumatoid arthritis (RA). However, the mechanism of CDH11 during RA-SFC proliferation is unclear. The aim of our study was to clarify the involvement of CDH11 and ß-catenin signalling during proliferation. METHODS: IL-1ß-induced and tumour necrosis factor-α (TNF-α)-induced cell proliferation, with CDH11 siRNAs, ß-catenin-specific siRNAs and a CDH11-neutralizing antibody, were assessed by 5-Bromo-2'-deoxy-uridine ELISA. KEY FINDINGS: Using CDH11 siRNAs, there were a 42% reduction in IL-1ß-induced proliferation and a 64% reduction in ß-catenin protein. When ß-catenin siRNAs were applied, there was a 63% reduction in IL-1ß-induced proliferation. The median effective concentration (EC50 ) values for IL-1ß-induced proliferation via CDH11-mediated ß-catenin-dependent, total ß-catenin-dependent and ß-catenin-independent signalling were 0.0015, 0.016 and 0.18 ng/ml, respectively. Blocking CDH11 ligation with a CDH11-neutralizing antibody did not decrease IL-1ß-induced proliferation. CONCLUSIONS: CDH11-mediated ß-catenin signalling was 42% involved in IL-1ß-induced proliferation and had the highest susceptibility to IL-1ß among the proliferative signallings analysed in this study. The mode of action for CDH11 during the cell proliferation was likely associated with a pool of ß-catenin protein. In contrast, CDH11 and ß-catenin were not involved in TNF-α-induced RA-SFC proliferation.

IL-10 enhances the phenotype of M2 macrophages induced by IL-4 and confers the ability to increase eosinophil migration.

M2 macrophages have been subdivided into subtypes such as IL-4-induced M2a and IL-10-induced M2c in vitro. Although it was reported that IL-10 stimulation leads to an increase in IL-4Rα, the effect of IL-4 and IL-10 in combination with macrophage subtype differentiation remains unclear. Thus, we sought to clarify whether IL-10 enhanced the M2 phenotype induced by IL-4. In this study, we showed that IL-10 enhanced IL-4Rα expression in M-CSF-induced bone marrow-derived macrophages (BMDMs). Global gene expression analysis of M2 macrophages induced by IL-4, IL-10 or IL-4 + IL-10 showed that IL-10 enhanced gene expression of M2a markers induced by IL-4 in M-CSF-induced BMDMs. Moreover, IL-4 and IL-10 synergistically induced CCL24 (Eotaxin-2) production. Enhanced CCL24 expression was also observed in GM-CSF-induced BMDMs and zymosan-elicited, thioglycolate-elicited and naive peritoneal macrophages. CCL24 is a CCR3 agonist and an eosinophil chemoattractant. In vitro, IL-4 + IL-10-stimulated macrophages produced a large amount of CCL24 and increased eosinophil migration, which was inhibited by anti-CCL24 antibody. We also showed that IL-4 + IL-10-stimulated (but not IL-4 or IL-10 alone) macrophages transferred into the peritoneum of C57BL/6J mice increased eosinophil infiltration into the peritoneal cavity. These results demonstrate that IL-4 + IL-10-simulated macrophages have enhanced M2a macrophage-related gene expression, CCL24 production and eosinophil infiltration-inducing activity, thereby suggesting their contribution to eosinophil-related diseases.

Two of four alternatively spliced isoforms of RUNX2 control osteocalcin gene expression in human osteoblast cells.

Runx2 is a Runt domain transcription factor that transcriptionally regulates osteoblast differentiation and bone formation. In this study, we show that human chondro- and osteosarcoma cell lines, human mesenchymal stem cells (hMSC) and a human primary chondrocytes (HC), osteoblst cells (HOb) express an intact isoform (RUNX2wt) and 3 alternatively spliced isoforms (RUNX2Delta5, Delta7, and Delta5Delta7) that are generated by skipping exon 5 and/or exon 7. Two of the truncated forms of RUNX2 (RUNX2Delta5 and RUNX2Delta5Delta7) did not localize in the nucleus and had lost their DNA binding activity. In cotransfection experiments with an osteocalcin (OC) promoter construct, we confirmed that only RUNX2wt and RUNX2Delta7 could upregulate the OC promoter activity in the osteosarcoma cell line. In addition, the coactivator CBP/p300 enhanced the transcriptional activity of the OC promoter when coexpressed with RUNX2wt or RUNX2Delta7, but not when coexpressed with RUNX2Delta5 or RUNX2Delta5Delta7. In contrast, the corepressor HDAC3 only repressed the activation from the OC promoter when coexpressed with RUNX2wt. These results support the hypothesis that RUNX2 both up- and downregulates its target gene promoters, as exemplified by the OC gene, using various isoforms and context-dependent formation of transcriptional complexes.