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To the editor, Asthma, one of the most common chronic diseases in childhood, is caused by interactions between genes and environmental factors. Since the IL-33/IL1RL1 pathway has been associated with eosinophilic, type 2, inflammation, we hypothesized that I IL1RL1 i SNPs may affect corticosteroid treatment response in asthma patients. No association between I IL1RL1 i and questionnaire-based asthma control was found. [Extracted from the article]

C and E, Genes upregulated in nasal brushes after ICS treatment are significantly enriched among genes upregulated in bronchial biopsies of asthma patients after ICS treatment (both FDR < 0.01). D and F, Genes downregulated in nasal brushes after ICS treatment are significantly enriched among genes downregulated in bronchial biopsies of asthma patients after ICS treatment (both FDR < 0.01). In summary, we show that nasal gene expression is dynamic, changes with ICS treatment in asthma patients and can be used as a proxy for the lower airways to investigate ICS-induced gene expression changes. [Extracted from the article]

Introduction: Asthma‐chronic obstructive pulmonary disease (COPD) overlap (ACO) is a heterogenous condition with clinical features shared by both asthma and COPD. Objectives: This online global survey of respiratory/allergy specialists and primary care practitioners (PCPs) was performed to understand current clinical approaches to the differential diagnosis and management of asthma, COPD and ACO. Methods: Respondents were recruited through: (a) a global online physician respondent community (49,980 PCPs and 7205 specialists); (b) market research agents; (c) experts; (d) professional societies; (e) colleague invitation. Respondents were presented with a survey including hypothetical clinical scenarios of diagnostic uncertainty to identify management approaches. Results: 891 responses (447 PCPs and 444 specialists) were collected across 13 countries. Reported features used for diagnosis of asthma and COPD were consistent with practice guidelines, but there was variability in those selected for ACO diagnosis. Features typically selected by specialists focused on spirometry/history, while PCPs focused on previous treatment/symptoms. Most respondents could correctly diagnose patients with features of ACO; however, features selected for theoretical diagnosis were often different to those selected in the case scenarios. Additionally, treatment selection was often inconsistent with guidelines, with over half of respondents not recommending inhaled corticosteroids in a patient with ACO and dominant features of asthma. Conclusion: While most PCPs and respiratory/allergy specialists can reach a working diagnosis of ACO, there remains uncertainty around which diagnostic features are most important and what constitutes optimal management. It is imperative that clinical studies including patients with ACO are initiated, allowing the generation of evidence‐based management strategies. [ABSTRACT FROM AUTHOR]

Background and objective: Inflammation is present to a variable degree and composition in patients with COPD. This study investigates associations between both eosinophils and neutrophils in blood, sputum, airway wall biopsies and bronchoalveolar lavage (BAL) and their potential use as biomarkers for clinical response to inhaled corticosteroids (ICS). Methods: In total, 114 steroid‐naïve COPD patients of the Groningen Leiden Universities Corticosteroids in Obstructive Lung Disease (GLUCOLD) study using ICS or placebo during 30‐month follow‐up were included. Cell counts in blood, sputum, biopsies and BAL were evaluated at baseline. In addition, at baseline, 6 and 30 months, forced expiratory flow in 1 s (FEV1), residual volume/total lung capacity (hyperinflation) and Clinical COPD Questionnaire were evaluated. Results: Cross‐sectional analyses at baseline showed that higher blood eosinophils were significantly associated with higher eosinophil counts in sputum, biopsies and BAL. However, blood neutrophils did not significantly correlate with neutrophil counts in the other compartments. Baseline eosinophils and neutrophils, in whichever compartment measured, did not predict longitudinal FEV1 changes. Higher baseline biopsy eosinophils were associated with an increase in symptoms during 6‐ and 30‐month ICS treatment. In addition, higher biopsy neutrophils were associated with a more marked reduction in hyperinflation during 6‐month ICS treatment compared with placebo. Conclusion: Our findings indicate that blood eosinophils reflect eosinophils in other compartments, in contrast to neutrophils, in ICS‐naïve COPD patients. Both baseline eosinophils and neutrophils do not predict ICS‐induced lung function changes over a period of 6–30 months. The associations of biopsy eosinophils with worsening respiratory symptoms and biopsy neutrophils with improvement in hyperinflation during ICS treatment deserve further investigation. See Letter Blood eosinophils, in contrast to neutrophils, reflect eosinophils in sputum, biopsies and bronchoalveolar lavage (BAL), in inhaled corticosteroids (ICS)‐naïve COPD patients. However, both baseline eosinophils and neutrophils, whether measured in blood, sputum, biopsies and BAL, insufficiently predict lung function response to ICS in COPD over a period of 6–30 months. [ABSTRACT FROM AUTHOR]

Abstract: Inflammation and ageing are intertwined in chronic obstructive pulmonary disease (COPD). The histone deacetylase SIRT1 and the related activation of FoxO3 protect from ageing and regulate inflammation. The role of SIRT1/FoxO3 in COPD is largely unknown. This study evaluated whether cigarette smoke, by modulating the SIRT1/FoxO3 axis, affects airway epithelial pro‐inflammatory responses. Human bronchial epithelial cells (16HBE) and primary bronchial epithelial cells (PBECs) from COPD patients and controls were treated with/without cigarette smoke extract (CSE), Sirtinol or FoxO3 siRNA. SIRT1, FoxO3 and NF‐κB nuclear accumulation, SIRT1 deacetylase activity, IL‐8 and CCL20 expression/release and the release of 12 cytokines, neutrophil and lymphocyte chemotaxis were assessed. In PBECs, the constitutive FoxO3 expression was lower in patients with COPD than in controls. Furthermore, CSE reduced FoxO3 expression only in PBECs from controls. In 16HBE, CSE decreased SIRT1 activity and nuclear expression, enhanced NF‐κB binding to the IL‐8 gene promoter thus increasing IL‐8 expression, decreased CCL20 expression, increased the neutrophil chemotaxis and decreased lymphocyte chemotaxis. Similarly, SIRT1 inhibition reduced FoxO3 expression and increased nuclear NF‐κB. FoxO3 siRNA treatment increased IL‐8 and decreased CCL20 expression in 16HBE. In conclusion, CSE impairs the function of SIRT1/FoxO3 axis in bronchial epithelium, dysregulating NF‐κB activity and inducing pro‐inflammatory responses. [ABSTRACT FROM AUTHOR]

Background Animal data have suggested that the transient receptor potential ankyrin-1 ( TRPA1) ion channel plays a key role in promoting airway inflammation in asthma and may mediate effects of paracetamol on asthma, yet confirmatory human data are lacking. To study associations of TRPA1 gene variants with childhood asthma and total IgE concentration, and interactions between TRPA1 and prenatal paracetamol exposure on these outcomes. Methods We analysed associations between 31 TRPA1 single nucleotide polymorphisms ( SNPs) and current doctor-diagnosed asthma and total IgE concentration at 7.5 years in the Avon Longitudinal Study of Parents and Children ( ALSPAC) birth cohort. We sought to confirm the most significant associations with comparable outcomes in the Prevention and Incidence of Asthma and Mite Allergy ( PIAMA) and Generation R birth cohorts. In ALSPAC, we explored interactions with prenatal paracetamol exposure. Results In ALSPAC, there was strong evidence for association between six SNPs and asthma: rs959974 and rs1384001 (per-allele odds ratio for both: 1.30 (95% CI: 1.15-1.47), p = 0.00001), rs7010969 ( OR 1.28 (1.13-1.46), p = 0.00004), rs3735945 ( OR 1.30 (1.09-1.55), p = 0.003), rs920829 ( OR 1.30 (1.09-1.54), p = 0.004) and rs4738202 ( OR 1.22 (1.07-1.39), p = 0.004). In a meta-analysis across the three cohorts, the pooled effect estimates confirmed that all six SNPs were significantly associated with asthma. In ALSPAC, TRPA1 associations with asthma were not modified by prenatal paracetamol, although associations with IgE concentration were. Conclusion This study suggests that TRPA1 may play a role in the development of childhood asthma. (249 words) [ABSTRACT FROM AUTHOR]

TGF-β is important in lung injury and remodeling processes. TGF-β and Wingless/integrase-1 (WNT) signaling are interconnected; however, the WNT ligand-receptor complexes involved are unknown. Thus, we aimed to identify Frizzled (FZD) receptors that mediate TGF-β-induced profibrotic signaling. MRC-5 and primary human lung fibroblasts were stimulated with TGF-β1, WNT-5A, or WNT-5B in the presence and absence of specific pathway inhibitors. Specific small interfering RNA was used to knock down FZD8.In vivostudies using bleomycin-induced lung fibrosis were performed in wild-type and FZD8-deficient mice. TGF-β1 induced FZD8 specifically viaSmad3-dependent signaling in MRC-5 and primary human lung fibroblasts. It is noteworthy that FZD8 knockdown reduced TGF-β1-induced collagen Iα1, fibronectin, versican, α-smooth muscle (sm)-actin, and connective tissue growth factor. Moreover, bleomycin-induced lung fibrosis was attenuated in FZD8-deficient mice in vivo. Although inhibition of canonical WNT signaling did not affect TGF-β1-induced gene expression in vitro, noncanonical WNT-5B mimicked TGF-β1-induced fibroblast activation. FZD8knockdown reduced both WNT-5B-induced gene expression of fibronectin and α-sm-actin, as well as WNT-5B-induced changes in cellular impedance. Collectively, our findings demonstrate a role for FZD8 in TGF-β-induced profibrotic signaling and imply that WNT-5B may be the ligand for FZD8 in these responses. [ABSTRACT FROM AUTHOR]

Background and objective Small airway dysfunction is associated with asthma severity and control, but its association with airway inflammation is unknown. The aim was to determine the association between sputum inflammatory cells and the site of small airway dysfunction, measured by multiple breath nitrogen washout in convection-dependent (Scond) and more peripheral diffusion-dependent ( Sacin) airways. Methods Fifty-three (20-67 years) subjects with asthma on inhaled corticosteroid ( ICS) treatment were characterized by spirometry, Scond, Sacin and induced sputum differential counts. %Predicted values for Scond and Sacin were calculated from published reference equations to adjust for the effects of age. Univariate correlations were assessed using the Spearman test. Multivariate linear regressions were performed to account for potential confounders, including age, gender, disease duration, body mass index and ICS dose. Results Sacin (%predicted) correlated significantly with neutrophil% (rs = 0.33, P = 0.02), ICS dose (rs = −0.28, P = 0.04) and age (rs = 0.27, P = 0.05). In multivariate analysis, Sacin related only to neutrophil% (adjusted R2 = 0.18, P = 0.001). Scond (%predicted) correlated significantly only with eosinophil% (rs = 0.39, P = 0.004). There was a trend for a negative relationship with ICS dose (rs = −0.26, P = 0.06). In multivariate analysis, Scond related to eosinophil% and ICS dose independently (adjusted R2 = 0.12, P = 0.02). Conclusions Acinar and conductive airway dysfunction is associated with different inflammatory profiles in asthmatic airways, independently of the effects of age and disease duration. The association between acinar airway dysfunction and neutrophilic airway inflammation may have implications for asthma treatment. [ABSTRACT FROM AUTHOR]

The soluble cleaved urokinase plasminogen activator receptor (scuPAR) is a circulating protein detected in multiple diseases, including various cancers, cardiovascular disease, and kidney disease, where elevated levels of scuPAR have been associated with worsening prognosis and increased disease aggressiveness. We aimed to identify novel genetic and bio-molecular mechanisms regulating scuPAR levels. Elevated serum scuPAR levels were identified in asthma (n=514) and chronic obstructive pulmonary disease (COPD; n=219) cohorts when compared to controls (n=96). In these cohorts, a genome-wide association study of serum scuPAR levels identified a human plasma kallikrein gene (KLKB1) promoter polymorphism (rs4253238) associated with serum scuPAR levels in a control/asthma population (P = 1.17x 10-7), which was also observed in a COPD population (combined P = 5.04 x 10-12). Using a fluorescent assay, we demonstrated that serum KLKB1 enzymatic activity was driven by rs4253238 and is inverse to scuPAR levels. Biochemical analysis identified that KLKB1 cleaves scuPAR and negates scuPAR's effects on primary human bronchial epithelial cells (HBECs) in vitro. Chymotrypsin was used as a proproteolytic control, while basal HBECs were used as a control to define scuPAR-driven effects. In summary, we reveal a novel post-translational regulatory mechanism for scuPAR using a hypothesis-free approach with implications for multiple human diseases. [ABSTRACT FROM AUTHOR]

Background and objective We assessed whether co-deposition of a long-acting β2-agonist and a corticosteroid affects their respective transport rates across epithelial cells. Methods Drug particles were deposited on the air-interface culture of Calu-3 cells using a twin-stage impinger. We compared the transport rate of salmeterol and fluticasone across the epithelial cells using commercially available formulations ( Serevent, Flixotide and Seretide). The transepithelial resistance of Calu-3 cells was measured before and after each deposition to monitor epithelial resistance. Results The codeposition of salmeterol and fluticasone had no significant effect on transport of salmeterol through the cell layer. In contrast, the rate of fluticasone propionate transport in presence of salmeterol xinofoate was significantly lower (0.53 ± 0.20%) compared with the single fluticasone formulation (2.36 ± 0.97%). Furthermore, the resistance of the epithelial cells was significantly increased after salmeterol deposition from both single and combination products. Conclusions Our data demonstrate that salmeterol may decrease the permeability of epithelial cells, resulting in slower fluticasone transport across Calu-3 epithelial monolayers. The subsequent increased residence time of fluticasone in the airways could prolong its anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

Background: Chronic lung diseases such as asthma, COPD and pulmonary fibrosis are characterized by abnormal extracellular matrix (ECM) turnover. TGF-β is a key mediator stimulating ECM production by recruiting and activating lung fibroblasts and initiating their differentiation process into more active myofibroblasts. Glycogen synthase kinase-3 (GSK-3) regulates various intracellular signalling pathways; its role in TGF-β₁-induced myofibroblast differentiation is currently largely unknown.Purpose: To determine the contribution of GSK-3 signalling in TGF-β₁-induced myofibroblast differentiation.Experimental Approach: We used MRC5 human lung fibroblasts and primary pulmonary fibroblasts of individuals with and without COPD. Protein and mRNA expression were determined by immunoblotting and RT-PCR analysis respectively.Results: Stimulation of MRC5 and primary human lung fibroblasts with TGF-β₁ resulted in time- and dose-dependent increases of α-sm-actin and fibronectin expression, indicative of myofibroblast differentiation. Pharmacological inhibition of GSK-3 by SB216763 dose-dependently attenuated TGF-β₁-induced expression of these myofibroblasts markers. Moreover, silencing of GSK-3 by siRNA or pharmacological inhibition by CT/CHIR99021 fully inhibited the TGF-β₁-induced expression of α-sm-actin and fibronectin. The effect of GSK-3 inhibition on α-sm-actin expression was similar in fibroblasts from individuals with and without COPD. Neither smad, NF-κB nor ERK1/2 were involved in the inhibitory actions of GSK-3 inhibition by SB126763 on myofibroblast differentiation. Rather, SB216763 increased the phosphorylation of CREB, which in its phosphorylated form acts as a functional antagonist of TGF-β/smad signalling.Conclusion and Implication: We demonstrate that GSK-3 signalling regulates TGF-β₁-induced myofibroblast differentiation by regulating CREB phosphorylation. GSK-3 may constitute a useful target for treatment of chronic lung diseases. [ABSTRACT FROM AUTHOR]

Background Chronic lung diseases such as asthma, COPD and pulmonary fibrosis are characterized by abnormal extracellular matrix ( ECM) turnover. TGF-β is a key mediator stimulating ECM production by recruiting and activating lung fibroblasts and initiating their differentiation process into more active myofibroblasts. Glycogen synthase kinase-3 ( GSK-3) regulates various intracellular signalling pathways; its role in TGF-β1-induced myofibroblast differentiation is currently largely unknown. Purpose To determine the contribution of GSK-3 signalling in TGF-β1-induced myofibroblast differentiation. Experimental Approach We used MRC5 human lung fibroblasts and primary pulmonary fibroblasts of individuals with and without COPD. Protein and m RNA expression were determined by immunoblotting and RT-PCR analysis respectively. Results Stimulation of MRC5 and primary human lung fibroblasts with TGF-β1 resulted in time- and dose-dependent increases of α-sm-actin and fibronectin expression, indicative of myofibroblast differentiation. Pharmacological inhibition of GSK-3 by SB216763 dose-dependently attenuated TGF-β1-induced expression of these myofibroblasts markers. Moreover, silencing of GSK-3 by si RNA or pharmacological inhibition by CT/CHIR99021 fully inhibited the TGF-β1-induced expression of α-sm-actin and fibronectin. The effect of GSK-3 inhibition on α-sm-actin expression was similar in fibroblasts from individuals with and without COPD. Neither smad, NF-κB nor ERK1/2 were involved in the inhibitory actions of GSK-3 inhibition by SB126763 on myofibroblast differentiation. Rather, SB216763 increased the phosphorylation of CREB, which in its phosphorylated form acts as a functional antagonist of TGF-β/smad signalling. Conclusion and Implication We demonstrate that GSK-3 signalling regulates TGF-β1-induced myofibroblast differentiation by regulating CREB phosphorylation. GSK-3 may constitute a useful target for treatment of chronic lung diseases. [ABSTRACT FROM AUTHOR]

Transforming growth factor β (TGF-β), a key mediator of fibrotic responses, is increased in asthma and drives airway remodeling by inducing expression of extracellular matrix (ECM) proteins. We investigated the molecular mechanisms underlying TGF-β-induced ECM expression by airway smooth muscle cells and demonstrate a novel link between TGF-β and Wingless/integrase 1 (WNT) signaling in ECM deposition. Airway smooth muscle expresses abundant WNT ligands, with the noncanonical WNT-5A being the most profoundly expressed. Interestingly, WNT-5A shows ∼2-fold higher abundance in airway smooth muscle cells isolated from individuals with asthma than individuals without asthma. WNT-5A is markedly induced in response to TGF-β (4–16-fold; EC50 0.3 ng/ml) and is required for collagen and fibronectin expression by airway smooth muscle. WNT-5A engages noncanonical WNT signaling pathways, as inhibition of Ca2+ and c-Jun N-terminal kinase (JNK) signaling attenuated this TGF-β response, whereas the canonical WNT antagonist Dickkopf 1 (DKK-1) did not. Accordingly, WNT-5A induced JNK phosphorylation and nuclear translocation of nuclear factor of activated T cells c1 (NFATc1). Furthermore, silencing of the WNT-5A receptors Frizzled 8 (FZD8) and RYK attenuated TGF-β-induced ECM expression. Collectively, these findings demonstrate that noncanonical WNT-5A signaling is activated by and necessary for TGF-β-induced ECM production by airway smooth muscle cells, which could have significance in asthma pathogenesis. [ABSTRACT FROM AUTHOR]

To cite this article: Vijverberg SJH, Koster ES, Koenderman L, Arets HGM, van der Ent CK, Postma DS, Koppelman GH, Raaijmakers JAM, Maitland-van der Zee A-H. Exhaled NO is a poor marker of asthma control in children with a reported use of asthma medication: a pharmacy-based study. Pediatr Allergy Immunol 2012: 23: 529-536. Abstract Background: A high fraction of nitric oxide in exhaled breath (FeNO) has been suggested to be a marker of ongoing airway inflammation and poorly controlled disease in asthma. The usefulness of FeNO to monitor asthma control is still debated today. Aim: To assess the validity of FeNO as a marker of asthma control in children with reported use of asthma medication. Methods: Fraction of nitric oxide in exhaled breath was measured in 601 children (aged 4-12 yr) with reported use of asthma medication in the past 6 months and in 63 healthy non-asthmatic children (aged 5-12). Asthma control was assessed by the Asthma Control Questionnaire (ACQ). A receiver-operator characteristics (ROC) curve was generated to assess the accuracy of FeNO as a marker for asthma control. Logistic regression analysis was used to study whether clinical, healthcare, medication, and environmental factors are associated with high FeNO levels (>25 ppb). Results: Fraction of nitric oxide in exhaled breath had a poor accuracy to discriminate well-controlled from not well-controlled asthma [area under the ROC curve: 0.56 (95% CI: 0.52-0.61, p = 0.008)]. In addition, high FeNO (>25 ppb) was associated with lower medication adherence rates (OR: 0.4; 95% CI 0.3-0.6), fewer antibiotic courses in the past year (OR: 0.6; 95% CI: 0.4-0.9), fewer leukotriene antagonists use in the past year (OR: 0.4; 95% CI: 0.2-0.9), and fewer visits to a (pulmonary) pediatrician (OR: 0.6; 95% CI: 0.4-0.9). Children living in a non-urban environment had more often high FeNO levels (OR: 1.7; 95% CI: 1.1-2.6). Conclusion: High FeNO is a poor marker of asthma control in children with reported use of asthma medication. Various other factors, including medication adherence and medication use, are associated with increased FeNO levels. [ABSTRACT FROM AUTHOR]

To cite this article: Koning H, Postma DS, Brunekreef B, Duiverman EJ, Smit HA, Thijs C, Penders J, Kerkhof M, Koppelman GH. Protocadherin-1 polymorphisms are associated with eczema in two Dutch birth cohorts. Pediatr Allergy Immunol 2012: 23: 270-277. Abstract Background: Eczema and asthma share a common genetic background and show linkage to chromosome 5q31-33. Protocadherin-1 ( PCDH1) is located in this region and was identified as a susceptibility gene for bronchial hyper-responsiveness (BHR), a hallmark of asthma. PCDH1 encodes an adhesion molecule, expressed in airway and skin epithelium. We determined whether PCDH1 polymorphisms, previously associated with asthma or BHR, also associated with questionnaire and UK Working Party (UKWP) defined eczema. Methods: Four PCDH1 polymorphisms were genotyped in two Dutch birth cohorts, PIAMA (n = 967) and KOALA Birth Cohort Study (n = 1560). Association with eczema was determined by chi-square tests and generalized estimating equations (GEE). Results: Insertion deletion IVS3-116 was associated with development of UKWP eczema in PIAMA [age 4, OR = 1.90 (1.14-3.18)] and borderline with questionnaire-reported eczema in PIAMA [GEE, OR = 1.33 (0.98-1.81)]. Furthermore, IVS3-116 was associated with questionnaire-reported eczema in KOALA [age 1, OR = 1.44 (1.00-2.07)]. Pooled analysis of questionnaire-reported eczema of both cohorts resulted in a significant association of IVS3-116 with eczema [OR = 1.26 (1.01-1.58)]. Rs3822357 (A-allele) associated with protection for eczema in PIAMA only [questionnaires, OR = 0.19 (0.06-0.63)]. Conclusion: PCDH1 gene variant IVS3-116 associates with eczema in two independent birth cohorts. Combined with previous observations, this indicates a shared genetic susceptibility to BHR, asthma and eczema. [ABSTRACT FROM AUTHOR]

The article presents which explores the Mannan-binding lectin (MBL)2 polymorphisms related to the risk of Fever during neutropenia (FN) in children with acute lymphoblastic leukaemia (ALL) during maintenance treatment. The study uses a Chi-squared test to evaluate the genotype combination and haplotype distributions between the groups with and without FN. Results show that MBL2 low-producing genotypes and haplotypes do not influence the occurrence of FN.

Protocadherin-1 (PCDH1) is a novel susceptibility gene for asthma that is expressed in airway epithelium. We aimed to characterize PCDH1 mRNA transcripts and protein expression in primary bronchial epithelial cells and to determine regulation of PCDH1 during mucociliary differentiation. Total RNA and protein were isolated from human primary bronchial epithelial cells. PCDH1 transcripts were characterized by rapid amplification of cDNA ends in bronchial epithelial cells of 4 subjects. PCDH1 expression was quantified by quantitative RT-PCR and Western blotting in bronchial epithelial cells directly ex vivo and after air liquid interface (ALI) or submerged culture. We identified 5 novel exons on the 5' end and 1 exon on the 3' end of PCDH1. Novel transcripts showed major variation in expression of intracellular conserved motifs. Expression levels of PCDH1 transcripts encoding exon 1--2 were 4-fold higher, and transcripts encoding exon 3-- 4 were 15-fold higher in freshly isolated bronchial epithelial cells than in submerged cultures. PCDH1 mRNA (3- to 8-fold) and protein levels (2- to 3-fold) were strongly up-regulated during mucociliary differentiation of primary bronchial epithelial cells in ALI cultures. In summary, PCDH1 transcripts display remarkable variability in expression of conserved intracellular signaling domains. Enhanced PCDH1 expression levels strongly correlate with differentiation of bronchial epithelial cells. [ABSTRACT FROM AUTHOR]

ABSTRACT Aims We investigated whether variants in the serotonin transporter gene ( SLC6A4) influence smoking cessation rates using antidepressant therapy (i.e. bupropion and nortriptyline). Design Pharmacogenetic (secondary) analysis of a randomized, placebo-controlled efficacy trial of bupropion and nortriptyline for smoking cessation. Setting Single-centre study, Maastricht University, the Netherlands. Participants A total of 214 of 255 (84%) current daily smokers participating in a randomized controlled efficacy trial. Measurements Subjects were genotyped for three functional variants in SLC6A4 (5-HTTLPR, STin2, rs25531). Primary outcome measures were prolonged abstinence from weeks 4-12, 4-26 and 4-52. Secondary outcome measures included 7-day point prevalence abstinence at weeks 4, 12, 26 and 52. Findings Carriers of the 5-HTTLPR high-activity L-variant had higher prolonged cessation rates with bupropion than placebo [odds ratio (OR) = 1.44, 95% confidence interval (CI) = 1.01-2.05, P = 0.04]. Combining the three variants resulted in increased prolonged cessation rates for both bupropion and nortriptyline among carriers of four to five high-activity variants (bupropion: OR = 2.00, 95% CI = 1.21-3.29, P = 0.01; nortriptyline: OR = 1.91, 95% CI = 1.02-3.56, P = 0.04). Similar results were found for point prevalence abstinence. Conclusions Bupropion and nortriptyline seem to be more effective in smoking cessation among SLC6A4 high-activity variant carriers, probably by blocking the increased serotonin transporter activity, thereby increasing serotonin levels. Prospective studies have to assess if this can improve cessation rates when treatment is targeted at individuals based on their genotypes. [ABSTRACT FROM AUTHOR]

To cite this article: Koster ES, Raaijmakers JAM, Vijverberg SJH, Koenderman L, Postma DS, Koppelman GH, van der Ent CK, Maitland-van der Zee A-H. Limited agreement between current and long-term asthma control in children: the PACMAN cohort study. Pediatr Allergy Immunol 2011: 22: 776-783 Abstract Background: Several studies have shown that predictors of asthma treatment outcomes differ depending on the definition of the outcome chosen. This provides evidence that different outcomes studied may reflect distinct aspects of asthma control. To assess predictors of asthma control, we need firm outcome phenotypes. The aim of this study was to investigate the association between measurements of current and long-term asthma control. Methods: We included 527 children using inhaled corticosteroids participating in the Pharmacogenetics of Asthma medication in Children: Medication with ANti-inflammatory effects cohort. Current asthma control (previous week) was defined using the Asthma Control Questionnaire. Long-term asthma control was based on Global Initiative for Asthma guidelines. Not well-controlled asthma in a season was defined as ≥3 of the following items present in a season: (i) day-time or (ii) night-time symptoms, (iii) limitations in activities, and (iv) rescue medication use. Asthma control during (i) the previous season and (ii) the year preceding the pharmacy visit was used as long-term asthma control definitions. Current and long-term asthma control were compared to investigate agreement. Results: Long-term uncontrolled asthma rates were highest in autumn and winter (50%) and lowest in summer (32%) (p < 0.05). Overall agreement between current and long-term asthma control was limited (66% for previous season and 68% for previous year). Conclusion: Congruence between current and long-term asthma control was limited. Furthermore, we showed significant seasonal differences. It is therefore important to calculate asthma control over a longer period of time, instead of using current asthma control as indicator. [ABSTRACT FROM AUTHOR]

Background: Despite existing effective treatment options, asthma is uncontrolled in a considerable proportion of patients. The aim of this study was to identify determinants of uncontrolled asthma at age 8 in children participating in the PIAMA birth cohort study. Methods: One hundred seventy children using inhaled corticosteroids in the previous 12 months at age 8 were included. Uncontrolled asthma was defined as: ≥3 items present in the past month: (1) day-time or (2) night-time asthma symptoms, (3) limitations in activities, (4) rescue medication use, (5) FEV1 < 80% predicted and (6) unscheduled physician visits because of asthma. Binomial regression was performed to study five groups of determinants representing asthma control: child and parental characteristics, environmental factors, therapy adherence and parental perception towards medication use (Beliefs about Medicines Questionnaire). Results: Seventy seven children (45%) had uncontrolled asthma. Low maternal education (RR 1.6, 95% CI: 1.0-2.4) was associated with uncontrolled asthma. Parental necessity beliefs about medication use to maintain present and future health and parental concerns about potential adverse consequences of medication were also associated with uncontrolled asthma (RR 1.6, 95% CI: 1.1-2.2; and 1.6, 95% CI: 1.0-2.5, respectively). Conclusions: Environmental factors and therapy adherence were not associated with asthma control. In our cohort, uncontrolled asthma is associated with low maternal education and with strong parental beliefs about medication necessity and higher concern about potential side effects of medication. [ABSTRACT FROM AUTHOR]

Purpose This study was conducted to assess the validity of parental reported use of inhaled corticosteroids (ICS) in children. Methods ICS users were identified within the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study and the PIAMA pharmacy sub-cohort which is nested within the PIAMA study. Complete medication histories were available for the first 8 years of life for children within the PIAMA pharmacy sub-cohort. Parental reported ICS use was measured by using data from questionnaires. ICS use in the pharmacy records was determined by using the Anatomical Therapeutic Chemical (ATC) codes. The proportion of overall agreement and kappa statistics with their corresponding 95% confidence intervals were calculated to quantify agreement between self-reported medication use and pharmacy prescription data. Results At all ages overall agreement was very high (>97%) and Cohen's kappa's ranged from 0.80 to 0.88 which also reflects excellent agreement between parental reported use of ICS and pharmacy prescription data. Conclusions Our finding suggests that parental report of medication use is a reliable source of data to asses ICS use in children. The questionnaire-based medication data collected within the PIAMA study can be used to study asthma medication use in a large group of children. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Wheeze has many underlying pathophysiologies in childhood, but is the main reason for anti-asthma drugs prescription. This study was conducted to describe asthma medication use patterns among children in their first eight years of life. Longitudinal medication use data from 777 children participating in the PIAMA study were used. Medication patterns were described for four groups that started therapy before the third birthday, when the peak in prescriptions occurred in our cohort; short-acting β-agonists (SABA), inhaled corticosteroids (ICS), SABA + ICS or none of these. One third ( n = 255) of the children received a first SABA or ICS prescription before age 8. Only three children (1.2%) used medication continuously during follow-up. Of the children who started SABA, 53.8% discontinued within 1-2 years. Of the children who started ICS before age 3, 42.1% discontinued within 1-2 years and 31.6% received additional SABA. 41.5% of the children who started SABA + ICS used this short-term (≤1-2 years) and 21.5% long-term (≥3 years). Fifteen percent of children who did not start asthma therapy in their first 3 years of life did receive prescriptions between age 3 and 8. Children prescribed SABA + ICS before age 3 had the highest prevalence of hyper responsiveness at age 8, and similar prevalence of atopy as the other groups. Asthma medication is prescribed frequently in the first 8 years of life, particularly before age 3, and only few children use it continuously. ICS and SABA prescription occurs especially in those who were more likely to develop signs of asthma at age 8. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Snijders BEP, Stelma FF, Reijmerink NE, Thijs C, van der Steege G, Damoiseaux JGMC, van den Brandt PA, van Ree R, Postma DS, Koppelman GH. CD14 polymorphisms in mother and infant, soluble CD14 in breast milk and atopy development in the infant (KOALA Study). Pediatr Allergy Immunol 2010: 21: 541–549. © 2009 John Wiley & Sons A/S Different CD14 polymorphisms have been associated with atopic phenotypes in infants. In addition, CD14 genotypes of breastfeeding mothers have been associated with soluble CD14 (sCD14) levels in breast milk. The role of CD14 genotypes of infant and mother and their interaction with sCD14 levels in breast milk in atopy development remain to be established. We aimed to study the associations of CD14 single nucleotide polymorphisms (SNPs), and their interaction with breast milk sCD14, with atopy development until age two. In addition, we assessed whether levels of sCD14 in breast milk associated with SNPs in CD14. Four SNPs in CD14 gene were investigated in 698 infants and 188 mothers. Associations between these SNPs, sCD14 and atopy development were analyzed in multiple logistic or linear regression models. The CD14/-1619 SNP was associated with eczema. CC homozygotes showed a lower risk of eczema vs. TT homozygotes (adjusted odds ratio = 0.56, 95% confidence interval 0.33–0.96) in a co-dominant model. Breast milk sCD14 levels did not significantly modify the effect of the child’s CD14 genotype on atopy development (p interaction ≥0.10). Maternal CD14 SNPs were not significantly associated with sCD14 levels in breast milk (anova, p ≥ 0.48). We found only an association between CC homozygozity of SNP CD14/-1619 and eczema. Our data did not support a modifying role of breast milk sCD14 levels on the relationship between CD14 genotype and atopy development until age 2 yr. [ABSTRACT FROM AUTHOR]

Cigarette smoking is the main risk factor for the development of squamous cell lung carcinoma (SCC). However, the smoking-related molecular changes in SCC have not been studied. Gene expression studies in both histologically normal bronchial epithelium and SCC epithelial samples identified genes differentially expressed between current and ex-smokers. Subsequently, expression levels of the smoking-related genes in normal bronchial epithelium were compared with those in SCC cells, since we hypothesized that the smoking-induced changes would be also deregulated in SCC. Gene expression profiles were generated using Agilent whole human genome microarrays on laser-microdissected normal bronchial epithelium and SCC samples. Expression levels of 246 genes, mainly related to oxidative stress response, were significantly different between normal bronchial epithelium of current and ex-smokers. Such a differential gene expression profile did not exist in SCC cells of smokers and ex-smokers. Interestingly, when comparing SCC and normal bronchial epithelium from ex-smokers, the vast majority of these 246 genes were also deregulated in SCC. When comparing SCC with normal epithelium from smokers, 22% of the up-regulated genes showed a similar high expression in SCC whereas 79% of the down-regulated genes were even further reduced in SCC as compared to current smokers. The down-regulated genes included several tumour suppressor genes, such as C9orf9, INHBB, LRIG1, SCGB3A1, SERPINI2, STEAP3 and ZMYND10. Thus, our study shows that the majority of genes up-regulated in normal bronchial epithelium of current smokers show similar high expression levels in SCC, while down-regulated genes are even further repressed in SCC. Our data indicate that smoking-related changes in normal bronchial epithelial cells persist in malignant transformed squamous cells. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article discusses a study about the relation of the differences in diet and lifestyle at 7 years old to the difference in overweight prevalence at 8 years old among Dutch children who were either breastfed and formula-fed. The study involved 2,043 children whose breastfeeding history, diet and lifestyle data at 7 years, and height and weight at 8 years were recorded. Results showed that breastfed children tend to eat fruit and vegetables more often than the formula-fed group. The breastfed children also exhibited lower overweight risk.

Cigarette smoke is the principal risk factor for development of chronic obstructive pulmonary disease (COPD). Multidrug resistance-associated protein 1 (MRP1) is a member of the ATP-binding cassette (ABC) superfamily of transporters, which transport physiologic and toxic substrates across cell membranes. MRP1 is highly expressed in lung epithelium. This study aims to analyze the effect of cigarette smoke extract (CSE) on MRP1 activity. In the human bronchial epithelial cell line 16HBE14o−, MRP1 function was studied flow cytometrically by cellular retention of carboxyfluorescein (CF) after CSE incubation and MRP1 downregulation by RNA interference (siRNA). Cell survival was measured by the MTT assay. Immunocytochemically, it was shown that 16HBE14o− expressed MRP1 and breast cancer resistance protein. Coincubation of CSE IC50 (1.53% ± 0.22%) with MK571 further decreased cell survival 31% ( p, = 0.018). CSE increased cellular CF retention dose dependently from 1.7-fold at 5% CSE to 10.3-fold at 40% CSE (both p < 0.05). siRNA reduced MRP1 RNA expression with 49% and increased CF accumulation 67% versus control transfected cells. CSE exposure further increased CF retention 24% ( p = 0.031). A linear positive relation between MRP1 function and CSE-modulating effects ( r = 0.99, p =0.089) was shown in untransfected, control transfected, and MRP1 downregulated 16HBE14o− cells analogous to blocking effects with MRP1 inhibitor MK571 ( r = 0.99, p = 0.034). In conclusion, cigarette smoke extract affects MRP1 activity probably competitively in bronchial epithelial cells. Inhibition of MRP1 in turn results in higher CSE toxicity. We propose that MRP1 may be a protective protein for COPD development. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:243-251, 2007; Published online in Wiley InterScience (). DOI 10.1002/jbt.20187 [ABSTRACT FROM AUTHOR]

Landstra AM, Kauffman HF, Marike Boezen H, van Aalderen WMC, Zonderland J, Postma DS. The influence of intravenous hydrocortisone on cytokine levels in children with asthma.Pediatr Allergy Immunol 2005: 16: 299–305.© 2005 Blackwell MunksgaardNocturnal airway obstruction occurs frequently in childhood asthma and results from increased airway inflammation. Lymphocytes are believed to be key effector cells of airway wall inflammation, releasing pro-inflammatory mediators and cytokines. A previous study showed that hydrocortisone infusion, an effective anti-inflammatory treatment, improves nocturnal and daytime FEV1 values. This study in 16 children with moderate asthma was designed to assess whether there exists day and night differences in IL-4, IL-5, IL-8, and IFN-γ production of concanavaline A stimulated peripheral blood mononuclear cells. Furthermore, we investigated whether substitution of low serum cortisol levels with intravenous hydrocortisone would affect those parameters. Saline (as a placebo) or hydrocortisone (30 μg/m2 body surface area/24 h) was intravenously administered in a randomized, double blind, cross-over design. Measurements under saline or hydrocortisone infusions were separated by 1 wk. At 04:00 and 16:00 hours 10 ml blood was taken for determination of peripheral blood mononuclear cell isolation and stimulation, and an eosinophil count. Hydrocortisone infusion significantly reduced the nocturnal fall in FEV1. Median values of IFNγ, IL-4, IL-5, and IL-8 produced by peripheral blood mononuclear cells did not significantly differ at 04:00 and 16:00 hours, both with saline and hydrocortisone infusion. Our results suggest that FEV1 improvement is not due to suppression of circulating peripheral blood mononuclear cell activation. We hypothesize that it is rather due to its effect on local lung tissue epithelial and/or fibroblasts thereby reducing airway inflammation and vascular leakage. [ABSTRACT FROM AUTHOR]

Slebos DJ, Kauffman HF, Koëter GH, Verschuuren EAM, van der Bij W, Postma DS. Airway cellular response to two different immunosuppressive regimens in lung transplant recipients.Clin Transplant 2005 DOI: 10.1111/j.1399–0012.2005.00330.x© Blackwell Munksgaard, 2005A number of new immunosuppressive drugs have become available in transplant medicine. We investigated the effects of two different immunosuppressive protocols on bronchoalveolar lavage fluid cellular characteristics in 34 lung transplant recipients who were treated with anti-thymocyte globulin induction therapy, cyclosporine, azathioprine (AZA), and prednisolone (regimen I), compared with 17 recipients receiving basiliximab induction, tacrolimus, AZA, and prednisolone (regimen II). We performed bronchoalveolar lavages between 15 and 40 d post-transplantation, in stable clinical condition and no acute rejection, cytomegalovirus, and/or respiratory tract infection. The regimen II treatment was associated with a significantly lower percentage lavage fluid lymphocytes than with regimen I. The CD4/CD8 ratio was significantly higher with regimen II than with regimen I: 1.56 (range 0.41–2.16) and 0.33 (0.04–0.95) respectively; p < 0.001, mainly because of a lower percentage CD8+ cells with regimen II: 25% (12–51) vs. regimen I: 60% (34–77); p < 0.001. The percentage CD4+ CD25+ cells appeared lower with regimen II: 21% (10–88) vs. regimen I: 50% (0–87); p = 0.04. Overall survival was similar between the groups, whereas a beneficial trend in freedom of bronchiolitis obliterans syndrome was observed with regimen II. Airway lymphocyte subtypes are affected by the immunosuppressive protocol used. This observation should be taken into account when studying transplant recipients, and may contribute to our understanding of alloreactive airway disease. [ABSTRACT FROM AUTHOR]

Kerkhof M, Wijga A, Smit HA, de Jongste JC, Aalberse RC, Brunekreef B, Gerritsen J, Postma DS and the PIAMA study group. The effect of prenatal exposure on total IgE at birth and sensitization at twelve months and four years of age: The PIAMA study.Pediatr Allergy Immunol 2005: 16: 10–18.© 2005 Blackwell MunksgaardThere is increasing evidence that the development of the fetal immune system can be influenced by environmental exposurein utero. We investigated whether prenatal exposure is associated with a high neonatal total IgE level and sensitization at the age of 1 and 4 yr. Data from 1027 infants were collected in a Dutch birth cohort study (PIAMA study). Total IgE was measured in heel prick blood collected in the first week of life. Sensitization was defined as a specific IgE level in serum of≥0.35 IU/ml against house dust mite, cat, dog, milk or egg. Logistic regression analysis was performed to study independent relationships between risk factors and a high neonatal total IgE (≥0.50 IU/ml) or sensitization. A high neonatal total IgE was found in 12.2% of boys and 6.2% of girls. A dog at home during pregnancy was negatively associated with a high neonatal total IgE [odds ratio (95% CI) 0.5 (0.2–1.0)]. A cat at home [OR 0.6 (0.4–1.0) and maternal smoking (OR 0.4 (0.2–1.0)] were negatively associated with sensitization at 12 months, but not at 4 yr. The presence of older siblings, season of birth, birth weight, mode of delivery, gestational age and maternal age were not associated with a high neonatal total IgE or sensitization. The higher total IgE level and prevalence of sensitization at 4 yr in boys compared with girls was only present in children from allergic mothers. Our results suggest a short-lasting protective effect of prenatal exposure to pets on total IgE at birth and early sensitization. [ABSTRACT FROM AUTHOR]

van den Berg JWK, Slebos D-J, Postma DS, Dijkhuizen B, Koëter GH, Timens W, van der Bij W, Kauffman HF. Feasibility of sputum induction in lung transplant recipients. Clin Transplant 2004 DOI: 10.1111/j.1399-0012.2004.00237.x © Blackwell Munksgaard, 2004 Sputum induction (SI) is nowadays being applied as a non-invasive and safe method to investigate airway inflammation in pulmonary diseases. We investigated the feasibility of SI after lung transplantation (LTX), and compared sputum and bronchoalveolar lavage (BAL) cellular characteristics and interleukin-8 (IL-8) levels. Results were also compared with 11 healthy subjects. SI as performed between 26 and 1947 d after LTX in 19 recipients, was successful in 16 of 22 attempts (73%). Six patients failed to produce sputum after induction, mostly just post-LTX and with having a lower forced expiratory volume in 1 s (FEV1). The success rate in clinically stable patients after the first month post-LTX was 93%. Side-effects were absent. Sputum recovery, viability and squamous cell contamination were comparable between LTX patients and healthy subjects. In the LTX group, total cell counts, neutrophil percentages and IL-8 levels were much higher in SI than BAL (1.6 × 106/mL, 65.5% and 54.2 ng/mL vs. 0.1 × 106/mL, 3.0% and 0.01 ng/mL; p < 0.001). Although LTX-neutrophil percentages in SI and BAL correlated properly ( ρ = 0.72, p = 0.04), both techniques are not interchangeable. We conclude that sputum induction is feasible, well tolerated, and without major side-effects in stable patients after the first month post-LTX. Induced sputum may be a useful tool to study inflammatory changes of the airways after LTX, and because of the large quantity of neutrophils sampled, especially for further studies on the pathogenesis of bronchiolitis obliterans. [ABSTRACT FROM AUTHOR]

The cAMP-dependent pathway plays an important role in the regulation of T cell-mediated immune responses by inhibition of T cell proliferation, activation and production of Th1-like cytokines.Depending on costimulatory signals and on the activation status of T cells, cAMP also regulates the production of Th2-like cytokines, yet the mechanism is not completely defined. We investigated the effect of costimulation with IL-2 on cAMP-mediated inhibition of IL-5 secretion and the signaling pathways involved in these effects in freshly isolated, α-CD3/α-CD28-stimulated human T lymphocytes. We demonstrate that IL-2 counteracts the cAMP-mediated inhibitory effects on IL-5 secretion by the modulation of phosphoinositide 3-kinase (PI3-K)-dependent signaling. Our results indicate that phosphorylation of cAMP-responsive element-binding protein (CREB) and the activity of the small GTPase Rap1 are unlikely involved in the protective effect of IL-2. Instead, the effect of IL-2may be mediated by the PI3-K-dependent inactivation of the forkhead-related transcription factor FKHR-L1, down-regulation of p27 [ABSTRACT FROM AUTHOR]

1 The adenylyl cylase (AC)/cyclic monophosphate (cAMP) system is known to negatively regulate transcriptional activity of T cells, thereby possibly modulating T-cell-mediated responses at the sites of inflammation. Effects of cAMP have been widely studied in freshly isolated T cells and T-cell clones; yet, effects in differentiated Th1 and Th2 cells are largely unknown. 2 To obtain differentiated T helper cells, we activated naive T cells for 1 week in presence of IL-12 plus α-IL-4 to generate Th1-type cells and in the presence of IL-4 plus α-IL-12 to generate Th2-type cells. 3 We demonstrate that, in contrast to freshly isolated T cells, the production of Th2 (IFN-γ) and Th2 (IL-4, IL-5) cytokines in polarized T helper cells in not strictly controlled by the activation of AC/cAMP-linked &beta[SUB2]-adrenergic and prostaglandin (PG)-E[SUB2] receptors. 4 In Th2 cells, PGE[SUB2] could still activate the G[SUBs]protein-coupled AC/cAMP system and subsequently induced CREB phosphorylation, whereas PGE[SUB2] was unable to activate the cAMP-dependent pathway in Th1 cells. in both Th1 and Th2 cells, the induction of CREB phosphorylation by β[SUB2]-agonist fenoterol was impaired. 5 The loss of control over cytokine production by cAMP elevating agents in differentiated Th1 and Th2 subsets may have important implications for the regulation of Th1- and Th2-mediated diseases, in particular those associated with the ongoing immune responses. [ABSTRACT FROM AUTHOR]

The author reflects on the need for awareness of patients and physicians regarding the small airway disease (SAD) in asthma. He notes that small airways are important location of airway resistance in asthma. However, due to the difficulty to reach small airways, researchers are prevented to study the role of SAD in the management, diagnosis, and outcome of asthma. He also relates that it is an unknown fact SAD affects the patient's quality of life and perception of symptoms.

The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study was initiated in 1996. Children born to allergic mothers were enrolled in a double-blind placebo-controlled trial for evaluating the use of mite-impermeable mattress and pillow covers. Children born to allergic and non-allergic mothers were enrolled in a ‘natural history’ study to assess the role of environmental and dietary risk factors for the development of allergic disease in childhood. Recruitment started by distributing a validated screening questionnaire among >10,000 pregnant women during their first visit to a prenatal health clinic. Allergic mothers-to-be were invited to participate in the intervention study. Allergic, and a random sample of non-allergic, mothers-to-be were invited to participate in the ‘natural history’ arm of the study. In the intervention study, homes were visited before birth, 3 months after birth, and 12 months after birth for the collection of dust samples from floors and mattresses. In addition, the homes of about one-third of the children in the ‘natural history’ part of the study were visited for dust collection when the children were 3 months of age. The intervention study started with 855 participants and the ‘natural history’ study with 3,291 participants. Follow-up at 3 years of age has now been completed with satisfactory compliance (>90%). A medical investigation and home visit at 4 years of age are nearing completion. Preliminary results show that mite-allergen levels were lower than found in previous Dutch studies, and that the intervention measure had a significant effect on mite-allergen levels, without important clinical benefits up to age 2 years old. The allergic families lived in homes with fewer ‘triggers’ such as pets, smoking and carpets than the non-allergic families, regardless of the intervention. The ongoing PIAMA cohort study will probably reveal useful... [ABSTRACT FROM AUTHOR]

Summary T helper 2 (Th2) cytokines [interleukin (IL)-4 and IL-5] play a central role in the development of allergic immune responses. After allergen provocation, the expression of Th2 cytokines is rapidly up-regulated in atopy and asthma. IL-6 is a multifunctional cytokine that is able to direct Th2 immune responses and is secreted by multiple tissue cell types. This study shows that IL-6 induces up-regulation of IL-4 and IL-5 after short (5 min) preincubation periods in freshly isolated, α-CD3/α-CD28-stimulated T cells. After longer preincubation periods with IL-6 (12 and 24 hr), the priming effect on IL-4 production gradually disappears, whereas the effect on IL-5 becomes more pronounced. In contrast, a small but significant inhibitory effect is found on the production of the Th1 cytokine interferon-γ. Additional experiments indicate that the long-term priming effect of IL-6 on IL-5 production is dependent on IL-2 signalling. This is not the case for the short-term IL-6 effect on IL-5 secretion, where the p38 mitogen-activated protein kinase-dependent induction of activator protein-1 DNA-binding activity is involved, independent of signal transducer and activator of transcription 3 phosphorylation. In summary, these data demonstrate that the short-term and long-term priming effects of IL-6 on Th2 cytokine production are regulated by different mechanisms. [ABSTRACT FROM AUTHOR]

Summary Nitric oxide (NO) modulates human T-lymphocyte responses through several mechanisms. In the current study we show that interactions between NO and glutathione (GSH) metabolism are related to the selective persistent inhibition of interferon-γ (IFN-γ) production by NO, which we previously identified. T cells were exposed to NO using the NO-donor compound Spermine-nonoate (Sper) and activated using anti-CD3 plus anti-CD28 monoclonal antibodies. Persistent inhibition of IFN-γ by Sper was prevented by addition of the GSH precursor l-cysteine, which inhibits Sper induced GSH depletion. Subsets of cells were either susceptible (GSHlow ) or resistant (GSHhigh ) to NO-induced GSH depletion. The GSHlow subset was characterized by enhanced numbers of CD4+ cells, reduced numbers of activated cells as characterized by CD25 and CD69, and reduced numbers of memory (CD45RO+ ) cells relative to the GSHhigh population. Rather than directly affecting susceptibility to NO, these surface markers reflected different expression patterns. Particularly, the GSHlow subset was further characterized by decreased activity of the GSH synthesis related enzymes multi-drug resistance related protein (MRP)-1 and γ-glutamyltranspeptidase (γ-GT). Blocking γ-GT, using acivicin was shown to exacerbate NO-induced GSH depletion and NO-induced apoptosis. Since NO induced apoptosis selectively affects IFN-γ production these findings implicate GSH metabolism in the modulation and maintenance of the T helper (Th)1/Th2 balance. [ABSTRACT FROM AUTHOR]