Exhaled Breath Condensate Of Children Research Articles

Inflammatory markers in exhaled breath condensate in nonasthmatic children with food allergy

Allergy is a systemic inflammation; therefore, although the allergic symptom may be seen in a specific organ system, the effects of this inflammation may be seen in other organs. interleukin (IL) IL4, IL5 and IL13 are the major Th2 cytokines and e-cadherin is an epithelial barrier protein. The objective of this research was to assess indicators of inflammation specific to Th2 responses and proteins related to the protective barrier of the airway’s inner lining. These assessments were conducted using exhaled breath condensate (EBC), which provides insights into peripheral airway conditions of children suffering from food allergies. The study had 24 patients with food allergy and 24 control individuals younger than three years of age with no history of food reaction. The diagnosis of food allergy was based on food allergen-specific IgE and skin prick test positivity in our clinic and oral food testing in selected cases. EBC samples were obtained by Ecoscreen (Jaegar, Hoechberg, Germany). IL4, IL5, IL13 and E-cadherin levels were measured in these samples by enzyme linked immunoassay. The group of children with food allergies, consisting mainly of 14 girls, had a median age of 16 months, whereas the control group, which included 11 girls, had a median age of 15 months (p = 0.89). Comparing the two groups, children with food allergies exhibited notably lower levels of IL-13 in the EBC compared to the control group (median values of 59.14 and 76.36, respectively, p = 0.02). Conversely, the concentration of IL-4 in the EBC was significantly higher in children with food allergies (median values of 1.94 and 1.29, respectively, p = 0.003). However, the levels of IL-5 and e-cadherin showed no significant differences between the two groups (with p-values of 0.74 and 0.09, respectively) as shown in table . High level of IL-4 despite the low level of IL-13 in the EBC of children having food allergy may be indicative of an early inflammatory phase that is not yet in the effector phase. Studies about the evolution of this process later in life are needed to assess the role of airway inflammation in children with food allergy who develop asthma.

The miRNA-24, miRNA-21 expressions and matrix metalloproteinase-7 level in exhaled breath condensate of children with primary spontaneous pneumothorax

Bullous lung diseases may cause primary spontaneous pneumothorax (PSP) in children. The microRNAs (miRNAs) are non-coding RNAs that participate in regulation of inflammation and cancer. We hypothesized that children with bullous lung disease and PSP may have altered miRNA expressions in their exhaled breath condensates (EBCs). Therefore, a prospective study was performed to evaluate the miRNA-24 and 21 expression, and the matrix metalloproteinase-7 (MMP-7) levels in EBC of children with PSP. Children with PSP were evaluated for age, gender, clinical features and results of surgical treatment. EBC samples (500–1000 ml) were collected to evaluate the miRNA-21, 24 expressions, and MMP-7, and tissue-inhibitor-MMP-1 (TIMP-1) levels. miRNA expressions and MMP levels of patients were compared with healthy controls (control group (CG), n = 12). Subjects (n = 16) with a mean age of 15 years (10–19 years), and a male-to-female ratio of 14:2 were enrolled in this study. The most common presenting symptom was sudden chest pain (n = 14). In 62.5% of the cases an underlying bullous lung disease were detected. During an average of 16.6 months (1–60 months) follow up period, four subjects relapsed. The mean MMP-7 (1.74–1.57 ng ml−1), and TIMP-1 (1.92–1.84 ng ml−1) levels were similar between both groups (p > 0.05). miRNA-24 expression was significantly decreased in the PSP group, when compared to the CG (0.16–1 2−ΔΔCT, p < 0.05). In addition, the miRNA-21 expression was not different between the two groups (p > 0.05). In conclusion, the miRNA-24 levels were significantly decreased in children with PSP. Taken together, children with PSP, especially those with bullous disease, should be closely monitored in the long-term period.

Dietary Acid Load Modulation of Asthma-Related miRNAs in the Exhaled Breath Condensate of Children.

Individual nutrients and bioactive compounds have been implicated in the expression of microRNAs (miRNAs), which are related to inflammation and asthma. However, evidence about the impact of diet is scarce. Therefore, we aimed to assess the association between dietary acid load and asthma-related miRNA in the exhaled breath condensate (EBC) of school-aged children. This cross-sectional analysis included 150 participants aged 7 to 12 years (52% girls) from a nested case–control study, which randomly selected 186 children attending 71 classrooms from 20 public schools located in city of Porto, Portugal. Dietary data were collected by one 24 h-recall questionnaire. Dietary acid load was assessed using the potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores. Based on previous studies, eleven asthma-related miRNAs were chosen and analyzed in EBC by reverse transcription-quantitative real-time PCR. PRAL, NEAP and miRNAs were categorized as high or low according to the median. Logistic regression models were performed to assess the association between dietary acid load scores and miRNAs. Children in high dietary acid load groups (PRAL ≥ 14.43 and NEAP ≥ 55.79 mEq/day) have significantly increased odds of having high miR-133a-3p levels. In conclusion, higher dietary acid loads possibly modulate asthma-related miRNAs of school-aged children.

Are level of IL-13 and IL-4 predictive for formation of chronic inflammation in children with asthma?

Asthma diagnosis in young children may represent a clinical challenge. There are no standard prognostic and dia-gnostic methods. The aim of the study was to evaluate the clinical and prognostic assessment of IL-4 and IL-13 concentrations in children with recurrent wheezing. The study included 96 children with recurrent wheezing. 81 patients were diagnosed as transient wheezing, 15 patients with asthma, and 25 healthy children were selected as controls. The concentrations of IL-4 and IL-13 were analyzed in exhaled breath condensate (EBC) using an enzyme-linked immunosorbent assay (ELISA). Data analysis was performed using Statsoft Statistica Version 8 (Tulsa, OK) and the statistical program MedCalc version 17.2. Both IL-4 and IL-13 concentrations were significantly higher in DDA (21.13 pg/mL, 26.13 pg/mL, respectively) and TW (13.86 pg/mL, 18.3 pg/mL, respectively) groups as compared to healthy controls (3.37 pg/mL, 16.35 pg/mL, respectively; p<0.001), and the highest rates were observed in children with diagnosed asthma (p < 0.001, DDW vs TW, respectively). IL-4 concentration higher than 18.45 pg/mL (with sensitivity 86.7% and specificity 80%) and IL-13 concentration higher than 20.17pg/ /mL (with sensitivity 100% and specificity 76.7%) in EBC in children with wheezing recurrence can be considered as a possible predictor of asthma development. The concentration of the anti-inflammatory cytokines IL-4 and IL-13 were significantly increased in children with recurrent wheezing and the highest rates were found in asthma developing children. The concentrations of IL-4 and IL-13 in chil-dren with wheezing can be considered as a possible predictor of asthma development.

Is the composition of exhaled breath condensate a key to explain the course of COVID-19 in children?

IntroductionThe relative resistance of children to severe course of the novel coronavirus infection remains unclear. We hypothesized that there might be a link between this phenomenon and observation from our previous studies concerning an inhibitory or cytotoxic effect of exhaled breath condensate (EBC) on endothelial cell cultures in children.AimSince we could not find any data on the similar effect caused by EBC in adults, the aim of our study was to evaluate and compare the biological activity of EBC in adults and children in an experimental in vitro model. Furthermore, in order to identify a putative agent responsible for these properties of EBC in children, we attempted to analyse the composition of selected EBC samples.Material and methodsThe influence of EBC samples on metabolic activity of endothelial cell line C-166 was assessed using colorimetric tetrazolium salt reduction assay (MTT assay). Selected EBC samples were fractionated using size exclusion chromatography and subjected to mass spectrometry analysis.ResultsExhaled breath condensates in healthy children, but not in adults, revealed a cytotoxic effect on in vitro cell cultures. This effect was most significant in condensate fraction, which contained a prominent 4.8 kDa peak in the mass spectra.ConclusionsBreath condensates of healthy children contain the factor which reveals the inhibitory/cytotoxic effect on endothelial cell cultures. Although the physiological role of this agent remains unclear, its identification may potentially be useful in ongoing research on SARS-CoV-2/COVID-19.

Development and validation of exhaled breath condensate microRNAs to identify and endotype asthma in children.

Detection and quantification of microRNAs (miRNAs) in exhaled breath condensate (EBC) has been poorly explored. Therefore we aimed to assess miRNAs in EBC as potential biomarkers to diagnose and endotype asthma in school aged children. In a cross sectional, nested case control study, all the asthmatic children (n = 71) and a random sample of controls (n = 115), aged 7 to 12 years, attending 71 classrooms from 20 local schools were selected and arbitrarily allocated to the development or validation set. Participants underwent skin-prick testing, spirometry with bronchodilation, had exhaled level of nitric oxide determined and EBC collected. Based on previous studies eleven miRNAs were chosen and analyzed in EBC by reverse transcription-quantitative real-time PCR. Principal component analysis was applied to identify miRNAs profiles and associations were estimated using regression models. In the development set (n = 89) two clusters of miRNAs were identified. After adjustments, cluster 1 and three of its clustered miRNAs, miR-126-3p, miR-133a-3p and miR-145-5p were positively associated with asthma. Moreover miR-21-5p was negatively associated with symptomatic asthma and positively associated with positive bronchodilation without symptoms. An association was also found between miR-126-3p, cluster 2 and one of its clustered miRNA, miR-146-5p, with higher FEF25-75 reversibility. These findings were confirmed in the validation set (n = 97) where two identical clusters of miRNAs were identified. Additional significant associations were observed between miR-155-5p with symptomatic asthma, negative bronchodilation with symptoms and positive bronchodilation without symptoms. We showed that microRNAs can be measured in EBC of children and may be used as potential biomarkers of asthma, assisting asthma endotype establishment.

Periostin concentration in exhaled breath condensate in children with mild asthma

Objective Periostin is considered to be a marker of eosinophilic inflammation in patients with asthma. However, there are no literature data on exhaled breath condensate (EBC) periostin level in pediatric patients with asthma. The aim of this study was to analyze EBC periostin concentration in children with mild asthma and to evaluate the potential usefulness of EBC periostin level as a biomarker for the disease. Methods EBC and serum periostin concentrations were measured by enzyme-linked immunosorbent assay in 23 children with asthma and 23 healthy controls. Results EBC periostin concentration was 250- to 780-fold lower than that found in serum. No significant differences between serum nor EBC periostin concentration in asthmatics and the control group were showed. The comparison between children with Th2 and non-Th2 type of asthma did not show significant differences in periostin concentration, both in serum and EBC. Serum periostin concentration inversely correlated with BMI and age not only in asthma patients but also in controls. Conclusions In children with mild asthma, periostin may be measured not only in serum but also in EBC. The low periostin level in patients with mild asthma and lack of difference between asthmatic subjects and controls indicate that EBC periostin may not be useful as an asthma biomarker in this group.

Клінічне значення рівнів фосфоліпідів у конденсаті видихуваного повітря у дітей з бронхообструктивним синдромом

Клінічне значення рівнів фосфоліпідів у конденсаті видихуваного повітря у дітей з бронхообструктивним синдромом

Амінокислотний склад сироватки крові та конденсату видихуваного повітря у дітей з бронхіальною астмою

Амінокислотний склад сироватки крові та конденсату видихуваного повітря у дітей з бронхіальною астмою

Serum and exhaled breath condensate leptin levels in asthmatic and obesity children: a pilot study

Background: Recent studies have highlighted the possible involvement of leptin in inflammation. The leptin receptor is also expressed by alveolar macrophages, T lymphocytes and bronchial epitelial cells, suggesting a possible role in the cascade of airway inflammation. Objectives: The aim of the study was to evaluate the levels of leptin in exhaled breath condensate (EBC) from asthmatic, normal- and overweight children, in relationship with airway inflammation. Methods: 15 asthmatic non-obese children, 15 healthy non-asthmatic non-obese children, 11 obese children with asthma (OA) and 20 obese children without asthma (ONA) were enrolled. Body impedance of body weight, EBC collection, FeNO, spirometry and a blood sampling for serum leptin were assessed. Results: Leptin EBC levels were significantly higher (3.9 ng ml−1 ± 1.3) in overweight children than those obese with asthma (3.6 ng ml−1 ± 1.6; p = 0.97), non-owerweight asthmatics (2.2 ng ml−1 ± 1.2; p < 0.0001) and in healthy children (0.9 ng ml−1 ± 0.6; p < 0.001). Leptin EBC levels in asthmatic children were significantly higher than in healthy children (p = 0.05). Leptin serum levels were significantly higher in the overweight children compared with the asthmatics (12.7 ng ml−1 ± 13.2; p < 0.001) and the healthy group (11.1 ng ml−1 ± 11.2; p < 0.001). We observed a significant correlation between EBC-leptin levels and the serum-leptin levels (p = 0.001). No correlations were found between EBC-leptin levels, FeNO and lung function. Conclusions: This study shows that leptin is measurable in EBC in children and that EBC-leptin levels are significantly higher in the obese subjects and in asthmatic ones compared with healthy subjects. Leptin may therefore represent a non-invasive marker of non-specific airway inflammation in children.

Content of markers of respiratory tract remodeling in exhaled breath condensate in children suffering from bronchial asthma

Background: This study investigated to detect the content of remodeling markers of the respiratory tract in the exhaled breath condensate (EBC) of children with bronchial asthma (BA). Materials and Methods: The study was in clinical groups of children with BA were formed on the indices in sputum supernatant: the Group I - “a high risk group” of bronchial remodeling (37 patients with vascular endothelial growth factor (VEGF) more than 80 ng/ml, and matrix metalloproteinase-9 (MMP-9) more than 5.2 ng/ml), the Group II - “a moderate risk” of bronchial remodeling (41 patients with VEGF more than 80 ng/ml, and MMP-9 <5.2 ng/ml, or VEGF <80 ng/ml, and MMP-9 more than 5.2 ng/ml), the Group III - “a low risk” of bronchial remodeling (38 patients with VEGF did not achieve 80 ng/ml, and MMP-9 <5.2 ng/ml). Results: The results obtained enable to believe that in EBC of children with a high risk of bronchial remodeling was higher azoalbumin olysis (1.8 ml/h comparison of Group II - 1.5 ml/h, P = 0.038, and Group III - 1.4 ml/h, P = 0.007), high catalase activity (81.26 comparison of other group - 50.7, P = 0.06, and 47.07, P = 0.052 μmol/min/mg of protein). Furthermore, in the clinical Group I, the content of nitrogen monoxide metabolites (53.5 mcmol/L) comparison of Group II of children (48.7 mcmol/L, P = 0.28) and the Group III (41.7 mcmol/L, P = 0.085). Conclusions: In children with a “high risk” of respiratory tract remodeling more significant inflammatory process in the bronchi is found than in children with a “low risk.”

Serum tryptase level and inflammatory markers in exhaled breath condensate of children with exercise-induced symptoms.

The pathogenesis of exercise-induced bronchoconstriction (EIB) is poorly understood. To evaluate the biomarkers concentration in exhaled breath condensate (EBC) in schoolchildren with postexercise symptoms. We also evaluated changes in fractional exhaled nitric oxide (FeNO) value and the serum tryptase level after exercise. One hundred children with postexercise symptoms were included. Methacholine challenge testing (MCT) was performed at visit 2, and exercise challenge testing (ECT) was performed at visit 3. Before and after ECT serum tryptase levels and FeNO values were measured. EBC was collected after ECT from 10 randomly selected children from each group. The children were assigned to the following groups: ECT(+) MCT(+), ECT(+) MCT(-), ECT(-) MCT(+), ECT(-) MC(-). We measured the following molecules: eotaxin, interleukin (IL) 8, IL-1ra, IL-1 beta, IL-6, IL-1 alpha, IL-12(p40), IL-5, granulocyte-macrophage colony-stimulating factor, IL-7, IL-15, IL-4, IL-2, IL-10, tumor necrosis factor alpha, interferon gamma, IL-13, tumor necrosis factor beta, monocyte chemoattractant protein-1, IL-17A, macrophage inflammatory proteins-1 alpha, macrophage inflammatory proteins-1 beta, IL-12(p70), and regulated on activation, normal T-cell expressed and secreted by using a multiplex immunoassay. Prostaglandin E2 (PGE2), leukotriene B4, and cysteinyl leukotriene were analyzed by using separate enzyme-linked immunosorbent assay kits. In the MCT(+) group, a detectable level of IL4 in EBC and detectible levels of eicosanoids were seen in the ECT(+) group. We observed the opposite direction of ECT-induced changes in FeNO and serum tryptase concentrations in patients with detectable compared with patients without detectable levels of cytokines in EBC. We showed ECT-induced reduction in the tryptase level in patients with a nondetectable PGE2 level in EBC and an increase in tryptase levels in patients who had detectable levels of PGE2 in EBC. EBC was a useful method to estimate inflammation but only in children with symptoms and with EIB shown by a positive ECT. Children with a positive ECT had detectable levels of eicosanoids in EBC; the opposite direction of ECT-induced changes in FeNO and serum tryptase concentrations was observed. The results of above study confirm the role of mast cells and eicosanoids in the pathogenesis of EIB in children.

Increased angiogenic factors in exhaled breath condensate of children with severe asthma – New markers of disease progression?

Asthma progression is associated with airway remodeling and neo-vascularization. However, role of angiogenesis in these changes remains unclear and available data still incomplete. In this pilot study we verify usefulness of proteome profiler assay in screening of angiogenesis-related factors in exhaled breath condensates (EBC) collected from children with asthma. EBC samples from patients with mild or severe asthma and healthy controls were tested using protein array. In EBC samples from patients with severe asthma we have found large quantities of several angiogenesis regulators, including thrombospondin (TSP)-1, angiogenin, dipeptidyl peptidase (DPP) IV, matrix metalloproteinase (MMP)-9 and its inhibitor TIMP-1. Small amounts of angiopoietin (Ang)-2 and vascular endothelial growth factor (VEGF) were also present. In contrast to them, in EBC from mild asthma group we have detected TSP-1 and small quantities of Ang-2. EBC samples from healthy controls contained only TSP-1. Our preliminary report suggests that, since increased amounts of angiogenesis-related factors in EBC seem to correlate with asthma severity, they may be considered as convenient non-invasive markers of disease progression. However, further research is necessary.

Asymmetric dimethylarginine and related metabolites in exhaled breath condensate of children with cystic fibrosis.

Asymmetric dimethylarginine (ADMA) competitively inhibits nitric oxide synthase (NOS). Its levels in specimens from murine models and asthmatic patients are related to inflammation and oxidative stress. Patients with cystic fibrosis(CF) reportedly have higher arginase activity, lower NO production and NOS expression than healthy controls. The objective was to assess the role of ADMA and related metabolites as disease biomarkers in exhaled breath condensate (EBC) of pediatric CF patients, compared with age-matched healthy controls (HC). A longitudinal design was conceived and 34 CF patients (21 stable, 13 at the onset of exacerbation) and 16 HC were enrolled. All CF patients underwent clinical examination, spirometry and EBC collection at enrolment; the same tests were performed also after an antibiotic course in those patients with exacerbation. Metabolites levels in EBC were measured with an ultra-performance liquid chromatography and tandem mass spectrometry technique. All CF patients had ADMA levels (expressed as ratio to tyrosine) similar to those in HC (median 0.0112, IQR 0.0103-0.0120 and median 0.0114, IQR 0.0090-0.0128, respectively; P = 0.983), while a significant increase in the citrulline/tyrosine ratio was found in CF patients (median 0.6419, IQR 0.5738-0.6899 in CF vs median 0.4176, IQR 0.2986-0.5082 in HC; P = 0.00003). No differences in ADMA levels emerged between stable patients and those with exacerbation. ADMA and related aminoacids were measured simultaneously for the first time in EBC from CF patients. Higher citrulline/tyrosine ratios were found in CF children with normal ADMA levels, suggesting a dysregulated ADMA metabolism in these patients.

Inhaled corticosteroids do not reduce initial high activity of matrix metalloproteinase (MMP)-9 in exhaled breath condensates of children with asthma exacerbation: a proof of concept study.

Inhaled corticosteroids (ICS) are the key component of asthma treatment. However, it is unclear whether they could control the activity and level of matrix metalloproteinase (MMP)-9, which is an important factor in asthma-associated inflammation and airway remodeling. Therefore, the aim of this proof of concept study was to analyze the influence of increased doses of ICS on MMP-9 in exhaled breath condensates (EBC) of patients with allergic asthma exacerbation. Apart from MMP-9, the assessment concerned selected inflammation markers – exhaled nitric oxide (eNO) and cytokines (IL-8 and TNF).The study involved a small group (n = 4) of individuals with asthma exacerbation. The intervention concerned increased doses of ICS with β-mimetics for 4 weeks. In addition to clinical evaluation, eNO measurements and EBC collections were done before and after 4 weeks of intense ICS treatment. The biochemical assessment of EBC concerned MMP-9, IL-8 and TNF. The data were compared to results of healthy controls (n = 6).The initial levels of eNO, MMP-9 and TNF in EBC were higher in the asthma group than in controls. In all subjects IL-8 levels were below the detection limit. After 4 weeks of ICS treatment in all patients we observed improvement of clinical and laboratory parameters. Interestingly, despite reduction of eNO and TNF, the activity of MMP-9/EBC remained on the initial level.Practical relevance of our results is limited by a small group. Nevertheless, our data suggest that ICS, although sufficient to control symptoms and inflammatory markers, may be ineffective to reduce MMP-9/EBC activity in asthma exacerbation and, possibly, airway remodeling.

Cytokine profiling in exhaled breath condensate after exercise challenge in asthmatic children with post-exercise symptoms.

IntroductionMarkers of exhaled breath condensate (EBC) correlate with lung function impairment, airway remodeling and different aspects of the disease such as exercise-induced bronchoconstriction (EIB). Aim of the study was to determine the cytokine profile in EBC of children with asthma after an exercise treadmill challenge in order to obtain clinically useful information about mechanisms of EIB; also, to assess correlations between cytokine concentrations in EBC and clinical characteristics of the patients.Material and methodsThe study population consisted of 25 randomly selected children, aged 8 to 19 years, with asthma and EIB symptoms despite the use of control medications. Patients on the day of the study visit underwent fractional exhaled nitric oxide measurement (FeNO) and baseline spirometry, performed an exercise treadmill challenge (ETC), and EBC samples were obtained at the end of the ETC.ResultsIn asthmatic children with positive ETC, monocyte hemotactic protein-1 (MCP-1) and IL-16 adjusted to pre-EBC forced expiratory volume in 1 s (FEV1) were significantly higher compared to children with negative ETC (p = 0.022 and p = 0.017 respectively). After adjustment to pre-EBC FEV1 other cytokines (IL-4, IL-5, IL-6, IL-8, MIG, TNF-α) were not related to post-exercise changes in FEV1.ConclusionsWe observed a specific inflammatory profile in the airways of asthmatic children with bronchoconstriction induced by exercise. The concentration of cytokines in EBC depended on the post-exercise decrease in FEV1, which was measured by the area under the curve (AUC). MCP-1 and IL-16, adjusted to pre-EBC FEV1, were significantly higher in children with a positive exercise challenge compared to those with a negative one.

The analysis of volatile organic compounds in exhaled breath and biomarkers in exhaled breath condensate in children - clinical tools or scientific toys?

Current monitoring strategies for respiratory diseases are mainly based on clinical features, lung function and imaging. As airway inflammation is the hallmark of many respiratory diseases in childhood, noninvasive methods to assess the presence and severity of airway inflammation might be helpful in both diagnosing and monitoring paediatric respiratory diseases. At present, the measurement of fractional exhaled nitric oxide is the only noninvasive method available to assess eosinophilic airway inflammation in clinical practice. We aimed to evaluate whether the analysis of volatile organic compounds (VOCs) in exhaled breath (EB) and biomarkers in exhaled breath condensate (EBC) is helpful in diagnosing and monitoring respiratory diseases in children. An extensive literature search was conducted in Medline, Embase and PubMed on the analysis and applications of VOCs in EB and EBC in children. We retrieved 1165 papers, of which nine contained original data on VOCs in EB and 84 on biomarkers in EBC. These were included in this review. We give an overview of the clinical applications in childhood and summarize the methodological issues. Several VOCs in EB and biomarkers in EBC have the potential to distinguish patients from healthy controls and to monitor treatment responses. Lack of standardization of collection methods and analysis techniques hampers the introduction in clinical practice. The measurement of metabolomic profiles may have important advantages over detecting single markers. There is a lack of longitudinal studies and external validation to reveal whether EB and EBC analysis have added value in the diagnostic process and follow-up of children with respiratory diseases. In conclusion, the use of VOCs in EB and biomarkers in EBC as markers of inflammatory airway diseases in children is still a research tool and not validated for clinical use.

Prolonged Treatment with Inhaled Corticosteroids does not Normalize High Activity of Matrix Metalloproteinase-9 in Exhaled Breath Condensates of Children with Asthma

The airway remodeling in asthma is associated with increased amount of matrix metalloproteinase (MMP)-9. High levels of MMP-9 were found in mucosal biopsies, sputum and in exhaled breath condensates (EBC) of asthma patients. However, there are no data concerning real in vivo activity. Inhaled corticosteroids are effective in asthma control, but it is unclear, whether they only attenuate inflammation, or also protect against progressive remodeling of respiratory tract. Therefore, the aim of the study was to assess the amount and activity of MMP-9 in context of pro-inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor, TNF), measured in EBC of asthma-suffering children, treated with inhaled steroids. The study involved 27 children with asthma, continuously treated with inhaled fluticasone propionate, and 22 healthy controls. In addition to routine clinical screening, the selected cytokines in EBC were analyzed using Ultrasensitive ELISA, whereas activity of MMP-9 was assessed using a novel immunozymography method. Despite chronic treatment with inhaled steroids mean MMP-9/EBC activity in asthma group was significantly higher than in healthy controls. Moreover, high MMP-9/EBC in asthma-suffering children significantly correlated with IgE serum levels. The IL-6 and IL-8 concentration was below the detection limit in all EBC samples. TNF/EBC levels were similar in both, asthma and healthy children. We hypothesize that MMP-9 hyperactivity in asthma may be closely related to high IgE serum levels. Our results suggest that inhaled steroids may be ineffective to prevent asthma-associated airway remodeling. Finally, we emphasize the necessity of further research focused on MMP-9 inhibition in asthma treatment.

Exhaled nitric oxide correlates with IL-2, MCP-1, PDGF-BB and TIMP-2 in exhaled breath condensate of children with refractory asthma.

IntroductionThere is evidence that parameters obtained from exhaled breath condensate (EBC) reflect changes in the level of the airway lining fluid. The telation between exhaled nitric oxide (NO) and EBC inflammatory markers has not been analyzed in the context of the inflammatory profile in the airways in asthmatic children.AimTo show the cytokine profile in EBC of children with severe/refractory asthma as well as correlations between the fractional exhaled NO (FeNO) level and cytokine concentrations.Material and methodsThe study population consisted of eight children aged 8 to 17 years with IgE-dependent, severe/refractory asthma with a duration of at least 2 years. This was an observational study, the first consecutive eight patients with asthma symptoms on the day of the study visit, when EBC samples were obtained.ResultsThe inter-subject variability of study cytokines ranged from 8.6 to 54.6. Cytokines with coefficient of variation < 20% were: interferon-γ, interleukins IL-2, IL-7, IL-15, IL-16, monokine induced by interferon γ (MIG) and tumor necrosis factor α. We showed a significant positive correlation between the FeNO level and crucial mediators in asthma development and progression (IL-2, MCP-1), and potent markers of airway remodeling (PDGFBB, TIMP-2). All correlations between two different variables were controlled for the effects of age, forced expiratory volume in 1 s and number of asthma exacerbations during last 12 months.ConclusionsThe profiling of cytokine expression in EBC can be reproducibly performed in children with severe/refractory asthma. When treating asthma in children, the FeNO level should be monitored as a prevention strategy of the progression of the remodeling leading to refractory/severe asthma. Exhaled breath condensate may be a useful tool to phenotype asthma via a non-invasive approach.

Markers of Inflammation in the Breath in Paediatric Inflammatory Bowel Disease

Breath analysis and exhaled breath condensate (EBC) collection are simple and noninvasive processes whereby inflammatory mediators and other biomarkers can be assessed in diseases that affect the lung. It was hypothesised that markers of epithelial dysfunction and secretion, such as a low pH, 8-isoprostane, and release of epithelial factors such as trefoil factor 2 (TFF2) and mucin, would be elevated in the breath of those with inflammatory bowel disease (IBD). The aim was to compare the levels of these biomarkers in EBC and the fraction of expired nitric oxide (FENO) in children with Crohn disease (CD), in those with asthma, and in normal individuals in a pilot study. EBC was collected from patients in the 3 groups mentioned above in a cross-sectional design. pH, 8-isoprostane, TFF2, and mucin levels were measured in the EBC. Spirometry was performed in asthmatic patients and patients with IBD, whereas FENO and skin prick tests were performed in patients with IBD. Breath samples including EBC were collected from 80 patients (30 CD, 30 asthma, 20 controls). Compared with controls, EBC pH was lower in children with IBD (P < 0.0001) or asthma (P = 0.0041). 8-Isoprostane levels differed between the 3 groups (P < 0.05). EBC TFF2 was mainly less than the limit of detection, whereas mucin levels did not differ significantly between the 3 groups. FENO was measurable in children with IBD, but did not correlate with disease activity or serum markers of inflammation. A lower EBC pH may reflect inflammatory events either in the lung or systemically. 8-Isoprostane, FENO, and mucin were detected for the first time in the EBC of children with IBD. Further studies are required to assess the value of these assessments.