Monitoring the allergic inflammation

Montelukast treatment response according to eosinophil-derived neurotoxin level in children with allergic rhinitis

BACKGROUND

Eosinophil-derived neurotoxin (EDN) is an important biomarker of eosinophilic inflammation.

METHODS

This study evaluated Montelukast treatment response according to EDN concentration in children with perennial allergic rhinitis (PAR). Fifty-two children with PAR were recruited and took a combination of Montelukast (5mg) and Levocetirizine (5mg) "Mont/Levo Group" or only Montelukast (5mg) "Mont Group" for 4 weeks. All caregivers were instructed to record rhinitis symptoms for 4 weeks. EDN was measured before and after treatment.

RESULTS

Daytime nasal symptom scores (DNSS) significantly decreased in both the Mont/Levo (p = 0.0001; n = 20) and Mont Group (p < 0.0001; n = 20), but there were no significant differences between the two groups. EDN concentration also significantly decreased after treatment in both groups (p < 0.0001 and p < 0.001, respectively). For secondary analysis, children with a high initial EDN concentration (EDN ≥ 53 ng/mL) were placed in the "High EDN Group", while those with a lower initial EDN concentration (EDN < 53 ng/mL) were put in the "Low EDN Group". Both groups experienced significant reductions in DNSS after either treatment regimen (p < 0.0001 and p = 0.0027, respectively) but the High EDN Group had greater reductions. EDN concentrations in the High EDN Group decreased significantly from either treatment (p < 0.0001).

CONCLUSION

We found that children with AR and a high serum EDN concentration may respond well to Montelukast treatment. A therapeutic strategy using EDN concentrations in patients with AR to evaluate therapeutic response may help improve quality of care.

Eosinophils-from cradle to grave: An EAACI task force paper on new molecular insights and clinical functions of eosinophils and the clinical effects of targeted eosinophil depletion

Over the past years, eosinophils have become a focus of scientific interest, especially in the context of their recently uncovered functions (e.g. antiviral, anti-inflammatory, regulatory). These versatile cells display both beneficial and detrimental activities under various physiological and pathological conditions. Eosinophils are involved in the pathogenesis of many diseases which can be classified into primary (clonal) and secondary (reactive) disorders and idiopathic (hyper)eosinophilic syndromes. Depending on the biological specimen, the eosinophil count in different body compartments may serve as a biomarker reflecting the underlying pathophysiology and/or activity of distinct diseases and as a therapy-driving (predictive) and monitoring tool. Personalized selection of an appropriate therapeutic strategy directly or indirectly targeting the increased number and/or activity of eosinophils should be based on the understanding of eosinophil homeostasis including their interactions with other immune and non-immune cells within different body compartments. Hence, restoring as well as maintaining homeostasis within an individual's eosinophil pool is a goal of both specific and non-specific eosinophil-targeting therapies. Despite the overall favourable safety profile of the currently available anti-eosinophil biologics, the effect of eosinophil depletion should be monitored from the perspective of possible unwanted consequences.

Olfactory cleft mucus eosinophil-derived neurotoxin better reflects olfactory loss than blood eosinophil counts in patients with chronic rhinosinusitis

BACKGROUND

Eosinophils are associated with olfactory dysfunction in chronic rhinosinusitis (CRS) and eosinophil-derived neurotoxin (EDN) is a sensitive marker of intense eosinophil activation. This study aimed to analyze olfactory cleft mucus and olfactory mucosa EDN levels and their association with olfactory dysfunction in CRS.

METHODS

We prospectively recruited 150 patients with CRS electing endoscopic sinus surgery and 25 healthy controls. Both superior turbinate biopsy specimens and olfactory cleft mucus were collected to analyze EDN levels. Sniffin' Sticks test scores, olfactory cleft computed tomography (CT) scores, and olfactory cleft endoscopy scale (OCES) were obtained. Multivariable logistic regression analysis was applied to analyze the predictability of EDN levels for olfactory dysfunction in CRS.

RESULTS

Chronic rhinosinusitis with olfactory dysfunction presented significantly higher olfactory mucosa (p = 0.016) and olfactory cleft mucus (p < 0.001) EDN levels than CRS without olfactory dysfunction. Mucus EDN levels were positively correlated with blood eosinophils (r = 0.625, p = 0.002), olfactory cleft CT scores (r = 0.738, p < 0.001), and OCES (r = 0.605, p = 0.004) in CRS. Furthermore, mucus EDN levels were significantly negatively correlated with threshold, discrimination, and identification (TDI) (r = -0.688), olfactory threshold (r = -0.606), olfactory discrimination (r = -0.608), and olfactory identification (r = -0.697) scores. After adjusting for patient demographics and comorbidities, mucus EDN levels were significantly associated with olfactory dysfunction in CRS (odds ratio = 2.162; p = 0.027). Mucus EDN levels showed a significantly better performance for predicting olfactory dysfunction than blood eosinophil counts (area under the curve, 0.873 vs. 0.764, p = 0.024).

CONCLUSION

Olfactory cleft mucus EDN level may be a better biomarker for predicting olfactory dysfunction in CRS than blood eosinophil counts.

The Role of Eosinophil-Derived Neurotoxin and Vascular Endothelial Growth Factor in the Pathogenesis of Eosinophilic Asthma

Asthma is a chronic complex pulmonary disease characterized by airway inflammation, remodeling, and hyperresponsiveness. Vascular endothelial growth factor (VEGF) and eosinophil-derived neurotoxin (EDN) are two significant mediators involved in the pathophysiology of asthma. In asthma, VEGF and EDN levels are elevated and correlate with disease severity and airway hyperresponsiveness. Diversity in VEGF polymorphisms results in the variability of responses to glucocorticosteroids and leukotriene antagonist treatment. Targeting VEGF and eosinophils is a promising therapeutic approach for asthma. We identified lichochalcone A, bevacizumab, azithromycin (AZT), vitamin D, diosmetin, epigallocatechin gallate, IGFBP-3, Neovastat (AE-941), endostatin, PEDF, and melatonin as putative add-on drugs in asthma with anti-VEGF properties. Further studies and clinical trials are needed to evaluate the efficacy of those drugs. AZT reduces the exacerbation rate and may be considered in adults with persistent symptomatic asthma. However, the long-term effects of AZT on community microbial resistance require further investigation. Vitamin D supplementation may enhance corticosteroid responsiveness. Herein, anti-eosinophil drugs are reviewed. Among them are, e.g., anti-IL-5 (mepolizumab, reslizumab, and benralizumab), anti-IL-13 (lebrikizumab and tralokinumab), anti-IL-4 and anti-IL-13 (dupilumab), and anti-IgE (omalizumab) drugs. EDN over peripheral blood eosinophil count is recommended to monitor the asthma control status and to assess the efficacy of anti-IL-5 therapy in asthma.

Olfactory cleft mucus galectin-10 predicts olfactory loss in chronic rhinosinusitis

BACKGROUND

Eosinophils have been reported to be involved in the pathogenesis of olfactory fluctuation in chronic rhinosinusitis (CRS). Galectin-10 is more frequently associated with type 2 inflammation and potentially a sign of intense eosinophil activation.

OBJECTIVE

To explore olfactory cleft mucus and olfactory mucosa galectin-10 level and its association with olfactory dysfunction (OD) in CRS.

METHODS

We prospectively enrolled 50 patients with CRS and 15 healthy controls. Olfactory cleft mucus and superior turbinate biopsy specimens were collected to analyze galectin-10 levels and quantify tissue eosinophils. Psychophysical olfactory testing, olfactory cleft endoscopy scale, and olfactory cleft computed tomography scores were obtained. The predictability of galectin-10 levels for OD in patients with CRS was analyzed by multivariable logistic regression analysis.

RESULTS

Both olfactory cleft mucus and olfactory mucosa galectin-10 levels in patients with CRS with OD were significantly higher than those in patients with CRS without OD (all P < .001). Mucus galectin-10 levels were positively correlated with tissue eosinophils (r = 0.541, P = 0.002), olfactory cleft endoscopy scale (r = 0.498, P = 0.006), and olfactory cleft computed tomography scores (r = 0.432, P = 0.019) in patients with CRS. Mucus galectin-10 levels were negatively correlated threshold, discrimination, and identification (r = -0.589,  P = 0.001), olfactory threshold (r = -0.522, P = 0.003), olfactory discrimination (r = -0.488, P = 0.007), and olfactory identification (r = -0.466, P = 0.011) scores. After adjusting for patient demographics and comorbidities, mucus galectin-10 levels were significantly associated with OD in patients with CRS (odds ratio, 1.299; P = .008). Mucus galectin-10 levels greater than 8.975 ng/mL were the best predictor of OD in CRS.

CONCLUSION

Olfactory cleft mucus galectin-10 is highly associated with OD in CRS.

Quality over quantity; eosinophil activation status will deepen the insight into eosinophilic diseases

Eosinophil associated diseases have gained much attention recently because of the introduction of specific eosinophil targeted therapies. These diseases range from acute parasitic infections to chronic inflammatory diseases such as eosinophilic asthma. In eosinophilic asthma an increased eosinophil cell count in peripheral blood is the gold standard for determination of the pheno-/endotype and severity of disease. Despite a broad consensus there is concern on validity of this simple measurement, because the eosinophil compartment is far from homogenous. Multiple tissues harbour non-activated cells under homeostatic conditions and other tissues, normally devoid of eosinophils, become infested with these cells under inflammatory conditions. It will, therefore, be clear that eosinophils become differentially (pre)-activated at different tissue sites in homeostatic and inflammatory conditions. This complexity should be investigated in detail as it is 1) far from clear what the long-term side effects are that are caused by application of eosinophil targeted therapies in a "one size fits all" concept and 2) real-world data of eosinophil targeted therapies in asthma shows a broad variety in the treatment response. This review will focus on complex mechanisms of eosinophil activation in vivo to create a better view on the dynamics of the eosinophil compartment in health and disease both to prevent collateral damage caused by aberrant activation of eosinophils ánd to improve effectiveness of eosinophil targeted treatments.

Serum Levels of Eosinophil-Derived Neurotoxin, Platelet-Activating Factor and Vascular Endothelial Growth Factor in Adult Patients with Atopic Dermatitis-A Pilot Study

Atopic dermatitis (AD) is a chronic, highly pruritic, relapsing-remitting inflammatory skin disease. The etiology of AD has not been fully explained yet and complex interactions of various small molecules are still being taken into account. The aim of this research was to investigate the serum eosinophil-derived neurotoxin (EDN), platelet activating factor (PAF) and vascular endothelial growth factor (VEGF) concentrations in relation to the disease severity and pruritus intensity in adult patients with AD. This pilot study was performed on 30 participants (15 patients with AD and 15 healthy controls). Blood samples were taken to examine the serum levels of EDN, PAF and VEGF using the enzyme-linked immunosorbent assay (ELISA) test. The severity of disease was assessed by the Scoring Atopic Dermatitis (SCORAD) index. The intensity of pruritus, as a subjective symptom, was determined by the Visual Analogue Scale (VAS). Obtained results revealed that the EDN (p = 0.016) and VEGF (p = 0.032), but not PAF (p = 0.841) concentrations were significantly higher in patients with AD compared with those of the control group. There was positive correlation between the EDN level and the SCORAD index in patients with AD (r = -0.9, p = 0.037) which was not found for the PAF and VEGF levels. Circulating EDN, PAF and VEGF levels were not significantly correlated with the severity of pruritus. Our results suggest that the END and VEGF serum levels are significantly increased in patients with AD compared to control group. Moreover, EDN might be useful to reflect the severity of symptoms.

Randomised clinical trial and meta-analysis: mesalazine treatment in irritable bowel syndrome-effects on gastrointestinal symptoms and rectal biomarkers of immune activity

BACKGROUND

Low-grade immune activation in the gut is a potential treatment target in irritable bowel syndrome (IBS).

AIMS

To determine improvement in IBS symptoms after mesalazine treatment, and the utility of measures of immune activity in the rectal mucosa METHODS: This was a randomised, double-blind, placebo-controlled, parallel-arm, multicentre trial in subjects with IBS (Rome III criteria), with an eight-week treatment period of mesalazine 2400 mg or plcebo once-daily. The primary endpoint was the global assessment of satisfactory relief of IBS symptoms in ≥50% of weeks during intervention. IBS symptoms were also measured with the IBS severity scoring system; immune activity was measured by mucosal patch technology. A post hoc meta-analysis of randomised placebo-controlled trials of mesalazine in IBS was added.

RESULTS

Of 181 included patients, 91 received mesalazine and 90 received placebo. The primary endpoint was met by 32 (36%) patients after mesalazine and 27 (30%) after placebo (p = 0.40). There were no differences in response rates related to IBS subtype or post-infection symptom onset. More reduction of abdominal bloating was noted in the mesalazine group (p = 0.02). The meta-analysis showed no effect of mesalazine on IBS symptoms. No mucosal patch technology measure could predict response to mesalazine, and found no differences in the effects of intervention on levels of immune markers.

CONCLUSIONS

Mesalazine is ineffective in reducing IBS symptoms. Rectal measures of immune activity by the mucosal patch technology cannot predict a higher chance of response to mesalazine.

Serum Levels of Vascular Endothelial Growth Factor, Platelet Activating Factor and Eosinophil-Derived Neurotoxin in Chronic Spontaneous Urticaria—A Pilot Study in Adult Patients

Chronic spontaneous urticaria (CSU) is a skin disease characterized by the presence of wheals, angioedema, or both for at least 6 weeks. Although, CSU is often regarded as autoimmune in nature, its etiology is not fully explained and interactions between various small molecules are still taken under account. The aim of this research was to investigate the mean serum concentration of vascular endothelial growth factor (VEGF), platelet activating factor (PAF), and eosinophil-derived neurotoxin (EDN) in relation to the disease activity and pruritus intensity in adult patients with CSU. Fifteen patients with CSU and 15 healthy subjects participated in this pilot study. Blood samples were taken to examine the mean serum levels of VEGF, PAF, and EDN by the enzyme-linked immunosorbent assay test (ELISA). The Urticaria Activity Score (UAS7) and The Visual Analogue Scale (VAS) were used to assess the disease activity and the pruritus intensity, respectively. Obtained results revealed that VEGF, PAF, and EDN concentrations were higher in patients with CSU compared with those of the control group, but only for VEGF it was statistically significant (p = 0.008). However, levels of all investigated cytokines were not significantly correlated neither with the disease activity nor with the pruritus intensity. Our results showed higher serum levels of VEGF, PAF, and EDN among CSU patients which may highlight a functional role of these cytokines in the disease’s pathogenesis. In contrast, VEGF, PAF, or EDN might not be useful to reflect the severity of symptoms.

Oral cavity response to air pollutant exposure and association with pulmonary inflammation and symptoms in asthmatic children

Exposure to fine particulate matter (PM_2.5) and ozone (O₃) may lead to inflammation and oxidative damage in the oral cavity, which is hypothesized to contribute to the worsening of airway inflammation and asthma symptoms. In this panel study of 43 asthmatic children aged 5-13 years old, each child had 4 clinic visits with a 2-week interval between two consecutive visits. At each visit, saliva samples were collected and subsequently analyzed for interleukin 6 (IL-6) and eosinophil cationic protein (ECP) as biomarkers of inflammation and malondialdehyde (MDA) as a biomarker of oxidative stress in the oral cavity. At each visit, children were measured for fractional exhaled nitric oxide (FeNO) as a marker of pulmonary inflammation. Asthma symptoms of these children were measured using the Childhood Asthma Control Test (C-ACT). We found that an interquartile range (IQR) increase in 24-h average personal exposure to PM_2.5 measured 1 and 2 days prior was associated with increased salivary IL-6 concentration by 3.0% (95%CI: 0.2%-6.0%) and 4.2% (0.7%-8.0%), respectively. However, we did not find a clear association between personal O₃ exposure and any of the salivary biomarkers, except for a negative association between salivary MDA and O₃ exposure measured 1 day prior. An IQR increase in salivary IL-6 concentration was associated with significantly increased FeNO by 28.8% (4.3%-53.4%). In addition, we found that increasing salivary IL-6 concentrations were associated with decreased individual and total C-ACT scores, indicating the worsening of asthma symptoms. We estimated that 13.2%-22.2% of the associations of PM_2.5 exposure measured 1 day prior with FeNO and C-ACT scores were mediated by salivary IL-6. These findings suggest that the induction of inflammation in the oral cavity may have played a role in linking air pollution exposure with the worsening of airway inflammation and asthma symptoms.

Eosinophil cationic protein (ECP) correlates with eosinophil cell counts in the induced sputum of elite swimmers

Introduction

Swimming practice has been associated with eosinophilic inflammation, however, the underlying mechanisms are not fully understood. The eosinophil cationic protein (ECP) in induced sputum may be used as a potential biomarker to assess airway eosinophilic inflammation among elite swimmers. The objective of this study is to characterize ECP levels in sputum supernatant in elite swimmers and evaluate ECP as an eosinophilic inflammatory marker.

Material and methods

Elite swimmers annually screened in our department (n = 27) were invited to participate in this cross-sectional study. Swimmers who agreed to participate (n = 24, 46% girls) performed lung function and skin-prick tests. Induced sputum was also collected and analyzed for differential cell counts and ECP measurements in sputum supernatant (ImmunoCAPTM 100, ECP, Thermo Fisher Scientific, Uppsala, Sweden).

Results

The median ECP level was 15.60 μg/L (6.02-38.75 μg/L) and higher levels were found among boys (27.90 (11.20-46.30) μg/L vs 6.65 (2.82-22.80) μg/L, P = .02). In addition, ECP levels in the sputum supernatant were positively correlated with eosinophil cell counts in the induced sputum (r = 0.583, P = .08).

Conclusions

ECP levels correlated positively with eosinophil counts in the induced sputum in elite swimmers. The measurement of ECP in sputum supernatant may be a useful marker to assess and manage eosinophilic inflammatory changes in the airways of elite swimmers.

Increase in eosinophil-derived neurotoxin level in school children with allergic disease

Background

Eosinophils are major effector cells of allergic disease and excellent markers of eosinophilic inflammation. Accurate and reliable biomarkers are helpful in the diagnosis, treatment, and control of allergic disease.

Objective

This study aimed to investigate an alternate marker of eosinophilic inflammation, eosinophil-derived neurotoxin (EDN), in a number of allergic diseases.

Methods

Three hundred ninety-six elementary school-age children with various allergic conditions were recruited for this study. Subgroups included food allergies (FAs), atopic dermatitis (AD), bronchial asthma (BA), and allergic rhinitis (AR). EDN levels in these groups were compared to those in 93 healthy controls (HC).

Results

All subjects with allergic disease had elevated levels of serum EDN (median [interquartile range]: FA, 124.2 ng/mL [59.13–160.5 ng/mL]; AD, 110.8 ng/mL [57.52–167.9 ng/mL]; BA, 131.5 ng/mL [60.60–171.0 ng/mL]; AR, 91.32 ng/mL [46.16–145.0 ng/mL]) compared to HC (38.38 ng/mL [32.40–55.62 ng/mL]) (p < 0.0001). These elevated levels were consistent throughout the age range (6–12 years) of the healthy study subjects (p = 0.0679). EDN levels also correlated well with total immunoglobulin E (Rs = 0.5599, p < 0.0001). Looking at all individuals with an allergic disease, the area under the curve was 0.790.

Conclusions

Direct measures of eosinophilic inflammation are needed for accurate diagnosis, treatment, and monitoring of allergic diseases. EDN may be a worthy biomarker of eosinophil activity and a useful screening tool for allergic diseases including FA, AD, BA, and AR.

Isolation and characterization of eosinophils in bovine blood and small intestine

An effective method to isolate functional eosinophils from blood and tissues is required to analyze the multiple roles eosinophils play in innate immunity and tissue homeostasis. Highspeed cell sorting was used to isolate bovine eosinophils from blood polymorphonuclear (PMN) cells and from small intestine intraepithelial leukocytes. Eosinophils and neutrophils were purified from bovine blood with highspeed cell sorting after gating on autofluorescence (FL1) high and low PMN subpopulations. Highspeed sorting of intestinal eosinophils was accomplished by using a combination of positive (CD45⁺, CD11c^Low, side scatter^High) and negative (CD3^-) selection parameters. Eosinophils sorted from blood PMNs were 88.6 ± 5.8 % (mean + 1 SD; n = 4) pure and yielded significantly (p < 0.05) more RNA than purified neutrophils. Analysis of Toll-like receptor (TLR) gene expression and TLR ligand-induced pro-inflammatory cytokine (IL-1, IL-6, IL-8, and TNFα) gene expression demonstrated significant (p < 0.01) functional differences between blood eosinophils and neutrophils. Eosinophils varied between 14.7 % to 29.3 % of CD45⁺ IELs and purity of sorted intestinal eosinophils was 95 + 3.5 % (mean + 1SD; n = 5). A comparison of mucosal and blood eosinophils revealed significant (p < 0.01) differences in TLR gene expression, supporting the hypothesis that functionally distinct eosinophil populations are present in blood and tissues. In conclusion, highspeed cell sorting provides an effective method to isolate viable eosinophils from blood and tissues that can then be used for transcriptome analyses and in vitro function assays.

Low-dose mepolizumab is effective as an add-on therapy for treating long-lasting peripheral neuropathy in patients with eosinophilic granulomatosis with polyangiitis

OBJECTIVE

To assess the effectiveness of low-dose mepolizumab as an add-on therapy for treating peripheral neurological symptoms in eosinophilic granulomatosis with polyangiitis (EGPA).

METHODS

We prospectively studied 13 EGPA patients with conventional treatment-resistant peripheral neuropathy. Their symptoms (pain, numbness, and muscle weakness) were assessed on a visual analogue scale (VAS) before and after 12 months of mepolizumab therapy (100 mg every 4 weeks). Peripheral eosinophil levels and several biomarkers including urinary levels of eosinophil-derived neurotoxin (EDN) were measured before and after therapy.

RESULTS

VAS scores for pain and numbness significantly improved after 12 months of mepolizumab therapy (from 67.0 to 48.0, P = 0.012, and from 67.0 to 51.0, P = 0.017, respectively). However, the VAS score for muscle weakness did not improve (P = 0.36). There were significant correlations between treatment-related changes in urinary EDN levels from baseline to 6 months later and percent changes in the VAS scores of pain and numbness (r = 0.75, P = 0.020; r = 0.88, P = 0.002).

CONCLUSIONS

Treatment-resistant peripheral neuropathy in EGPA was significantly improved by low-dose mepolizumab, and effectiveness was correlated with decreased urinary EDN. Because the possibility of a placebo effect cannot be formally excluded, placebo-controlled studies will be required in the future.

Multimorbidity in asthma, association with allergy, inflammatory markers and symptom burden, results from the Swedish GA2 LEN study

Background

Asthma is common worldwide and a large part of subjects with asthma have concomitant allergic multimorbidity in the form of rhinitis and/or eczema.

Objective

The aim of this study is to investigate whether the presence of allergic multimorbidity in asthma relates to allergic sensitization, allergic and respiratory symptoms, quality of life, inflammatory markers, lung function, use of medication and background factors.

Methods

A total of 437 asthmatics from the (GA²LEN) cross‐sectional survey in Sweden were grouped depending on the presence of rhinitis and/or eczema. The impact of allergic multimorbidity was assessed in terms of allergic sensitization, allergic and respiratory symptoms, quality of life, type‐2 inflammatory markers (exhaled nitric oxide, eosinophil activation markers, periostin), lung function, use of medication and background factors.

Results

Subjects with asthma, rhinitis and eczema were more likely to be sensitized to seasonal allergens (67% vs 32%, P < .001), food allergens (54% vs 18%, P < .001) and to have a higher degree of sensitization than subjects with only asthma (23% vs 10%, P < .001). Subjects with allergic multimorbidity more often had allergic reactions to food (28% vs 10%, P = .002), more respiratory symptoms and anxiety/depression (40% vs, 14%, P < .001) than subjects with only asthma, despite having similar levels of type 2 inflammatory markers. Individuals with allergic multimorbidity were more likely to be diagnosed with asthma before the age of 12 (48% vs 27%, P = .016) and to have maternal heredity for allergy (53% vs 33%, P = .011) than subjects with only asthma.

Conclusion and clinical relevance

Asthmatics with allergic multimorbidity are more likely to be sensitized to seasonal aeroallergens, food allergens and they have a higher degree of sensitization compared with those with only asthma. Allergic multimorbidity is associated with respiratory and allergy symptoms, anxiety and/or depression.

In vitro and in vivo Antiallergic Effects of Taurine on Allergic Rhinitis

BACKGROUND

The current treatment for allergic rhinitis (AR) is inadequate.

OBJECTIVE

The present study aimed to investigate the therapeutic effect of taurine on AR and to identify the underlying molecular mechanisms.

METHODS

The serum level of the antioxidant enzyme extracellular superoxide dismutase (SOD3) was determined in AR patients and in healthy controls. The antiallergic inflammatory effects of taurine were evaluated in a dinitrophenyl-human serum albumin (DNP-HSA)-stimulated human mast cell line (HMC-1) and in an ovalbumin (OVA)-induced AR mouse model.

RESULTS

Clinically, a reduction in serum level of SOD3 was observed in AR patients. Taurine treatment led to dose-dependent increases in SOD3 at both protein and mRNA levels in HMC-1 cells. SOD3 production was regulated by peroxisome proliferator-activated receptor-γ (PPAR-γ) in response to taurine. SOD3 overexpression inhibited the release of proinflammatory cytokines including tumor necrosis factor-α (, interleukin (IL)-4, and IL-6. Its overexpression also ameliorated the loss of interferon-γ. SOD3 and PPAR-γ influenced inflammatory cytokine production via regulation of the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). An OVA-induced AR animal model study showed that taurine was efficacious in alleviating allergic inflammatory reactions by relieving behavior symptoms of AR mice and reducing eosinophilic and mast cell infiltration into the nasal cavity. In addition, taurine treatment increased the production of SOD3 and PPAR-γ, which, in turn, suppressed expression of proinflammatory cytokines through phosphorylation of ERK1/2.

CONCLUSION

Taurine could potentially serve as a therapeutic treatment for allergic disorders.

Serum Eosinophil-Derived Neurotoxin Better Reflect Asthma Control Status Than Blood Eosinophil Counts

BACKGROUND

Although several biomarkers have been proposed for eosinophilic asthma, biomarkers for reflecting asthma control status remain controversial. Eosinophil-derived neurotoxin (EDN), a degranulated eosinophil protein, is an emerging biomarker in asthmatic patients.

OBJECTIVE

This study analyzed serum EDN concentrations in asthmatics and compared its performance with that of blood eosinophil count as an indicator of asthma control status.

METHODS

We enrolled 75 uncontrolled asthmatics, 56 controlled asthmatics, and 43 healthy controls from Asan Medical Center. Serum EDN levels (ng/mL) were measured using an enzyme-linked immunosorbent assay kit. The predictability of EDN for asthma control status was analyzed by univariate and multivariable logistic regression analyses. A receiver operating characteristic (ROC) curve analysis was conducted to compare the performances of a serum EDN level and blood eosinophil count as indicators of uncontrolled asthma status.

RESULTS

The mean serum EDN level in the uncontrolled asthma group was higher than that in the controlled asthma and healthy groups (103.2 ± 60.2 vs 60.8 ± 49.7 vs 49.6 ± 28.3 ng/mL, P < .001). Serum EDN level was the significant parameter related to asthma control status in univariate and multivariable analysis (both P < .001). Serum EDN levels correlated with blood eosinophil counts (r = 0.510, P < .001). However, in the ROC analysis, serum EDN level showed a significantly better performance for predicting uncontrolled asthma status (area under the curve, 0.726 vs 0.628, P = .024).

CONCLUSIONS

Serum EDN levels significantly differed between patients with controlled and uncontrolled status in adult asthmatics. To our knowledge, this is the first study to identify EDN as a better indicator of asthma control status than blood eosinophil count.

Concurrence of elevated FeNO and airway hyperresponsiveness in nonasthmatic adolescents

OBJECTIVES

The aim of this study was to investigate airway responsiveness and eosinophil and neutrophil inflammatory markers in clinically confirmed nonasthmatic adolescents with elevated fractional exhaled nitric oxide (FeNO), a marker of type-2 inflammation in the airways.

METHODOLOGY

A total of 959 subjects from a general population, aged 12 to 15 years, answered a standardised questionnaire and underwent FeNO measurements at a screening visit at school. Adolescents without asthma, who had elevated FeNO (FeNO₁₀₀  > 15 ppb) (n = 19), and control subjects, with low FeNO (FeNO₁₀₀  < 5 ppb) and without reported symptoms of asthma or allergy (n = 28), participated in a follow-up study where FeNO₅₀ , airway responsiveness to methacholine (PD₂₀ ), blood eosinophil counts, and serum neutrophil lipocalin (HNL) and myeloperoxidase (MPO) levels were measured. Questionnaire follow-ups were performed 4 and 16 years later.

RESULTS

Airway responsiveness (PD₂₀ : 6.94 [1.87, 11.39] vs 11.42 [6.33, 59.4] µmol; P < .05) and blood eosinophil counts (0.31 [0.20, 0.44] vs 0.13 [0.1, 0.22] 10⁹ /L; P < .001) (geometric mean [95% CI]) were higher among cases than controls. A significant correlation between blood eosinophils and FeNO was found (rho = 0.41; P = .005). In contrast, serum HNL and MPO were lower in cases than controls (P < .05 both), and there was a negative correlation between HNL and FeNO (r = -0.31; P = .04). At both follow-ups, a higher proportion of subjects reported allergic symptoms compared with baseline (P = .02, P = .01).

CONCLUSIONS

Elevated FeNO in nonasthmatic adolescents was associated with airway hyperresponsiveness, elevated blood eosinophil counts, and lower systemic activation of neutrophils.

Eosinophils capture viruses, a capacity that is defective in asthma

Background

Activated eosinophils cause major pathology in stable and exacerbating asthma; however, they can also display protective properties like an extracellular antiviral activity. Initial murine studies led us to further explore a potential intracellular antiviral activity by eosinophils.

Methods

To follow eosinophil‐virus interaction, respiratory syncytial virus (RSV) and influenza virus were labeled with a fluorescent lipophilic dye (DiD). Interactions with eosinophils were visualized by confocal microscopy, electron microscopy, and flow cytometry. Eosinophil activation was assessed by both flow cytometry and ELISA. In a separate study, eosinophils were depleted in asthma patients using anti‐IL‐5 (mepolizumab), followed by a challenge with rhinovirus‐16 (RV16).

Results

DiD‐RSV and DiD‐influenza rapidly adhered to human eosinophils and were internalized and inactivated (95% in ≤ 2 hours) as reflected by a reduced replication in epithelial cells. The capacity of eosinophils to capture virus was reduced up to 75% with increasing severity of asthma. Eosinophils were activated by virus in vitro and in vivo. In vivo this correlated with virus‐induced loss of asthma control.

Conclusions

This previously unrecognized and in asthma attenuated antiviral property provides a new perspective to eosinophils in asthma. This is indicative of an imbalance between protective and cytotoxic properties by eosinophils that may underlie asthma exacerbations.

Development of an automated ImmunoCAP research assay for eosinophil derived neurotoxin and its use in asthma diagnosis in children

Background

Eosinophil Derived Neurotoxin (EDN) is an eosinophil granule protein that is released during eosinophil activation. EDN has proven to be a promising marker for eosinophilic inflammation both in asthma and in wheezing symptoms in children.

Objectives

Here we present a novel ImmunoCAP^TM automated immunofluorescence research assay for measurement of EDN and its potential use in diagnosis of asthmatic children.

Methods

We report the analytical performance of the assay in serum, heparin- and EDTA-plasma in terms of precision, linearity, sensitivity, interfering substances and specimen handling. We also compared the EDN research assay with established methods for asthma diagnosis: fraction of exhaled nitric oxide (FeNO) and blood eosinophil fraction (EOS%) to demonstrate the diagnostic value of EDN in childhood asthma.

Results

The total precision (measured using percentage CV) was ≤5.8% for both serum and plasma. The dilution analysis yielded linear results across the dynamic range of the assay for both serum and plasma. No notable interferences of endogenous substances were observed.

The median concentration of EDN was significantly higher in the asthma group compared to the healthy controls and the EDN correlates well with EOS%.

Conclusions

we have shown that EDN can be measured reliably and robustly with the ImmunoCAP platform in both serum and plasma samples. EDN can be used to distinguish asthmatic from healthy children and correlates well with EOS% and could be a valuable complement to both EOS% and FeNO.

Comparison of serum eosinophil-derived neurotoxin levels between wheezing and non-wheezing groups in children with respiratory tract infection

Objective: Eosinophil-derived neurotoxin (EDN) is associated with recurrent wheezing episodes after bronchiolitis, childhood asthma, and allergic rhinitis. We investigated if there is a measurable difference between serum EDN levels in children with wheezing and non-wheezing respiratory infections.Methods: 171 children who visited a university hospital with respiratory infections were enrolled in the study. Subjects were divided into two groups: wheezing (n = 46) and non-wheezing (n = 125). Serum EDN levels were compared.Results: Serum EDN levels in the wheezing group were significantly higher than in the non-wheezing group (P < 0.001). The non-wheezing group was divided into three sub-groups: pneumonia, common cold, and tonsillitis. Serum EDN levels in the wheezing group were significantly higher than in the pneumonia, common cold, or tonsillitis subgroups (P < 0.001). There was no significant difference in serum EDN levels among the pneumonia, common cold, and tonsillitis subgroups.Conclusions: These findings suggest that elevated serum EDN levels could be a distinctive feature of respiratory infections with wheezing. EDN's utility as a biomarker for wheezing-associated disease should be explored through further study.

Montelukast Reduces Serum Levels of Eosinophil-Derived Neurotoxin in Preschool Asthma

PURPOSE

Several markers for eosinophilic inflammation have been proposed to predict response to asthma treatment. However, definitive criteria for treatment decisions have not yet been established. We investigate a potentially useful relatively non-invasive biomarker, eosinophil-derived neurotoxin (EDN), to predict favorable responses to budesonide or montelukast, common treatment for children with asthma.

METHODS

Young children (1 to 6 years old) were enrolled in this randomized, parallel, 2-group, open-label trial. Criteria for eligibility included: 1) being symptomatic during the run-in period; and 2) having a serum EDN (sEDN) level ≥ 53 ng/mL, with positive specific immunoglobulin E to house dust mite. Eligible patients were randomly placed into 2 groups: the BIS group received budesonide inhalation suspension (BIS) 0.5 mg once daily; the MONT group received montelukast 4 mg once daily. Ineligible patients were invited to receive montelukast 4 mg once daily (OBS group). Treatment period was 12 weeks.

RESULTS

Asthma control days increased significantly in the BIS and MONT groups (P < 0.000) over the 12-week study period. There was no significant change in sEDN in the BIS group but there was a significant decrease in the MONT group (P < 0.000). Patients in the OBS group with high EDN levels (< 53 ng/mL) showed a significant decrease due to MONT treatment (P = 0.023). Rescue medication usage significantly decreased in the BIS and MONT groups (P < 0.000).

CONCLUSIONS

EDN is a useful relatively non-invasive biomarker for predicting responses to montelukast and budesonide treatment of preschool children with beta2-agonist responsive recurrent wheeze and multiple-trigger wheeze (Trial registry at UMIN Clinical Trials Registry, UMIN000008335).

Associations between self-rated health, sickness behaviour and inflammatory markers in primary care patients with allergic asthma: a longitudinal study

Allergic asthma is a chronic inflammatory disorder associated with elevated levels of immunoglobulin E (IgE), serum eosinophilic cationic protein (S-ECP), plasma eosinophil-derived neurotoxin (P-EDN) and fraction of exhaled nitric oxide (FENO). Poor self-rated health and sickness behaviour has repeatedly been associated with inflammatory markers, but the nature of this relationship in chronic inflammatory disease is not known. Likewise, such findings largely rely on cross-sectional investigations. Self-rated health (How would you rate your general state of health?), sickness behaviour (mean rating of satisfaction with energy, sleep, fitness, appetite and memory), IgE, S-ECP, P-EDN, and FENO were assessed in 181 non-smoking primary care patients with asthma in a 1-year longitudinal study. Associations between repeated measurements were calculated using mixed regression models and Spearman's correlations for change scores. Poor self-rated health was associated with high levels of seasonal IgE (p = 0.05) and food IgE (p = 0.04), but not total IgE or inflammatory markers. An increase over 1 year in perennial IgE was associated with a worsening of self-rated health (ρ = 0.16, p = 0.04). Poor self-rated health was associated with more pronounced sickness behaviour (p < 0.001), and a worsening in sickness behaviour was associated with a worsening of self-rated health over time (ρ = 0.21, p = 0.007). The study corroborates the importance of sickness behaviour as a determinant of self-rated health by showing that these factors co-vary over a 1-year period in a group of patients with allergic asthma. The importance of specific IgE for perceived health in primary care patients with mild to moderate asthma needs further investigation.

Utility of serum eosinophil-derived neurotoxin (EDN) measurement by ELISA in young children with asthma

BACKGROUND

This study was done to compare the efficacy of a recently developed eosinophil-derived neurotoxin (EDN) ELISA kit ("BioTracer™ K^® EDN ELISA Kit") to a commercially available EDN ELISA kit ("MBL EDN ELISA Kit") and demonstrate the usefulness of serum EDN measurement in young asthmatic children.

METHODS

Forty-eight children with physician-diagnosed asthma (Asthma group) and 31 age-matched normal controls (Control group) were recruited from the Asthma and Allergy Center at Inje University Sanggye Paik Hospital, Seoul, Korea from January 2010 to September of 2012. EDN levels in each serum specimen were measured 2 times using the: 1) BioTracer™ K^® EDN ELISA Kit and 2) MBL EDN ELISA Kit at the Inje University Sanggye Paik Hospital laboratory. EDN level measurements in each serum specimen were compared.

RESULTS

EDN measurements from the BioTracer™ K^® EDN ELISA Kit correlated well with those from the MBL EDN ELISA Kit: r = 0.9472 at the Inje University Sanggye Paik Hospital laboratory. These r values were considered both clinically relevant (i.e., r > 0.85) and statistically significant (p < 0.0001). EDN measurements from both kits positively correlated with asthma symptom severity (p < 0.0001). No serious adverse events occurred during the study.

CONCLUSIONS

The BioTracer™ K^® EDN ELISA Kit was accurate and useful in measuring EDN levels in young asthma patient serum. Because of our kit's distinct advantages and utility, we suggest this kit can be used for the timely diagnosis, treatment, and monitoring of asthma in asthma patients of all ages, especially those too young to perform pulmonary function tests.

Interaction between allergic asthma and atherosclerosis

Prior studies have established an essential role of mast cells in allergic asthma and atherosclerosis. Mast cell deficiency or inactivation protects mice from allergen-induced airway hyper-responsiveness and diet-induced atherosclerosis, suggesting that mast cells share pathologic activities in both diseases. Allergic asthma and atherosclerosis are inflammatory diseases that contain similar sets of elevated numbers of inflammatory cells in addition to mast cells in the airway and arterial wall, such as macrophages, monocytes, T cells, eosinophils, and smooth muscle cells. Emerging evidence from experimental models and human studies points to a potential interaction between the 2 seemingly unrelated diseases. Patients or mice with allergic asthma have a high risk of developing atherosclerosis or vice versa, despite the fact that asthma is a T-helper (Th)2-oriented disease, whereas Th1 immunity promotes atherosclerosis. In addition to the preferred Th1/Th2 responses that may differentiate the 2 diseases, mast cells and many other inflammatory cells also contribute to their pathogenesis by more than just T cell immunity. Here, we summarize the different roles of airway and arterial wall inflammatory cells and vascular cells in asthma and atherosclerosis and propose an interaction between the 2 diseases, although limited investigations are available to delineate the molecular and cellular mechanisms by which 1 disease increases the risk of the other. Results from mouse allergic asthma and atherosclerosis models and from human population studies lead to the hypothesis that patients with atherosclerosis may benefit from antiasthmatic medications or that the therapeutic regimens targeting atherosclerosis may also alleviate allergic asthma.

Effect of intranasal corticosteroid on pre-onset activation of eosinophils and mast cells in experimental Japanese cedar pollinosis

BACKGROUND

Minimal persistent inflammation (MPI) contributes to hyperreactivity in allergic rhinitis. However, little is known regarding whether pre-onset activation of eosinophils and mast cells is present or not in Japanese cedar pollinosis (JCP). Furthermore, a prophylactic effect of intranasal corticosteroids on such MPI in JCP has not been investigated.

METHODS

We designed a double-blinded, randomized, placebo-controlled, crossover trial. Twenty patients with JCP were examined outside the pollen season (UMIN000008410). Nasal provocation with paper discs containing extracts of Japanese cedar pollen was performed once a day for 3 consecutive days. Onset of nasal symptoms was monitored over 15 min after each provocation. The levels of eosinophil cationic protein (ECP) and tryptase in nasal secretions were examined. Fluticasone furoate nasal spray or placebo treatment was started one day before the first provocation.

RESULTS

In the placebo group, 25% of the patients showed onset of nasal symptoms following provocation on the first day. In addition, 75% and 68% of the patients showed symptom onset on the second and third day of provocation, respectively. After the first provocation, the levels of ECP and tryptase in nasal secretions were significantly increased. These increases were seen not only in symptomatic but also in asymptomatic subjects in response to provocation, and the levels were similar between these subjects. Prophylactic treatment with fluticasone significantly suppressed the increase in nasal ECP and tryptase associated with repeated provocations.

CONCLUSIONS

These results suggest that pre-onset activation of eosinophils and mast cells is present in experimental JCP, and that prophylactic treatment with intranasal corticosteroids has the potential to control such activation.

Harsh parent-child conflict is associated with decreased anti-inflammatory gene expression and increased symptom severity in children with asthma

Asthma is a chronic respiratory disorder that affects over 7 million children in the United States. Evidence indicates that family stressors are associated with worsening of asthma symptoms, and some research suggests that these stressful experiences engender changes in children's immune systems in ways that exacerbate airway inflammation and contribute to both acute and chronic asthma symptoms. We examined the association between observed experiences of parent-child conflict and the expression of signaling molecules involved in the transduction of anti-inflammatory signals that regulate airway inflammation and obstruction. Fifty-seven children and their parents participated in a conflict task, and coders rated interactions for evidence of harsh and supportive behaviors. Children reported on their perceptions of parental support and reported on their daily asthma symptoms for 2 weeks. We collected peripheral blood in children to measure leukocyte expression of messenger RNA for the glucocorticoid receptor and the β2-adrenergic receptor. Analyses revealed that harsh conflict behaviors were associated with decreased expression of both messenger RNAs and more severe asthma symptoms. Neither supportive behaviors nor perceived parental support was associated with gene expression or asthma symptoms. These findings suggest that harsh interactions with parents are associated with downregulation of key anti-inflammatory signaling molecules and difficulties breathing in children with asthma. Children with asthma who are also victims of maltreatment may be particularly susceptible to transcriptional changes in immune cells that could worsen asthma over time.

Effects of dietary Lactobacillus acidophilus and Bacillus subtilis on laying performance, egg quality, blood biochemistry and immune response of organic laying hens

The objective of this study was to evaluate the effects of two different probiotic micro-organisms on the performance, egg quality and blood parameters of organically reared hens. A total of 900 16-week-old Hy-Line layer hybrids were randomly assigned to three groups of 300 birds each. The control (CTR) group was fed a corn-soya bean cake-based diet; the L group was fed the same diet supplemented with 0.1% Lactobacillus acidophilus, while the B group was fed the same diet supplemented with 0.05% Bacillus subtilis. Data were recorded at the beginning (weeks 5 and 6: T1) and at the end (weeks 19 and 20: T2) of the experiment, and no differences in hen performance were recorded between dietary groups or sampling times. All of the investigated clinical chemistry parameters, except GGT, were affected by diet (p < 0.05), with the best results recorded for the probiotic-treated groups. The immune-response values showed higher blood bactericidal activity in the B and L groups at T2 (p < 0.05) and a lower lysozime concentration in the B group at T1. Higher antibody production against Newcastle disease virus was observed in the L group compared to the CTR (p = 0.013). No differences in oxidative status were recorded, and no effects of diet on egg quality were observed. Among the physical egg characteristics, only the Roche scale colour was affected by diet (p < 0.05): the egg yolk was paler in the L group. The age of the hen was the most relevant factor affecting physical egg characteristics. The chemical parameters of the egg were almost unaffected by supplementation with probiotics except for the lipid content, which decreased with the L diet (p < 0.05). Both probiotic inclusions had beneficial effects on hen metabolism and welfare, and L. acidophilus induced the best immune response.

Family Functioning, Eosinophil Activity, and Symptoms in Children With Asthma

OBJECTIVE

We examined prospective connections among parental depressive symptoms, family dysfunction, and eosinophil activity in children with asthma.

METHODS

81 children with asthma and their parents completed two laboratory visits across a 1-year period. At baseline and 1 year later, parents reported about their depressive symptoms and family dysfunction. We collected peripheral blood in children to measure eosinophil counts and eosinophil cationic protein. Following visits, children recorded their asthma symptoms for 2 weeks.

RESULTS

After controlling for demographic and biomedical covariates, a significant T1 × T2 Family Dysfunction interaction emerged, suggesting that the links between family dysfunction at T1 and eosinophil counts and activity at T2 depended on family functioning at T2. Parental depressive symptoms were unrelated to eosinophil activity and asthma symptoms.

CONCLUSIONS

These findings suggest that improvements in family functioning are associated with decreases in eosinophil activity, which may contribute to inflammatory processes that affect airway function.

Serial Changes in Serum Eosinophil-associated Mediators between Atopic and Non-atopic Children after Mycoplasma pneumoniae pneumonia

Purpose

Mycoplasma pneumoniae pneumonia (MP) is associated with the exacerbation, timing, and onset of asthma. The goal of this study was to elucidate the impact of MP on eosinophil-related hyper-reactive amplification in atopic children.

Methods

We studied 48 patients with MP (26 atopic, 22 non-atopic), between 3 and 12 years of age. Serial changes in blood eosinophil counts, serum interleukin-5 (IL-5), and serum eosinophil cationic protein (ECP) levels were measured in atopic and non-atopic children with MP upon admission, recovery, and at 2 months post-recovery. Serum IL-5 and ECP levels were measured by enzyme-linked immunosorbent assays; eosinophil counts were measured using an autoanalyzer.

Results

Serial changes in serum IL-5, ECP, and total eosinophil counts were significantly higher in atopic patients, relative to non-atopic controls (P≤0.001). Serum IL-5 and ECP levels were significantly higher in atopic patients at all three time points tested, while eosinophil counts were higher in the clinical recovery and follow-up phases, but not in the acute phase. Furthermore, among atopic patients, serum ECP levels were significantly higher in the recovery and follow-up phases than in the acute phase.

Conclusions

The present study demonstrated significant differences in eosinophil counts, serum IL-5, and serum ECP levels between atopic and non-atopic children with MP at admission, recovery, and 2 months after clinical recovery. These outcomes are suggestive of eosinophil-related hyperreactivity in atopic children, with this status maintained for at least 2 months after MP.

The production of the eosinophil proteins ECP and EPX/EDN are regulated in a reciprocal manner

Previous studies showed that the biological activity and the eosinophil content of eosinophil cationic protein (ECP, RNase 3) are determined by single-nucleotide polymorphisms (SNPs) in the ECP (RNase3) gene. In this study, we report the prevalence of a common SNP in the eosinophil protein x/eosinophil-derived neurotoxin (EPX/EDN, RNase2) and the association with the cellular contents of EPX/EDN and ECP. The genes were sequenced and the EPX/EDN405(G>C) rs2013109 SNPs were also determined by TaqMan 5′nuclease allelic discrimination assay. ECP and EPX/EDN in purified eosinophils or in whole blood extracts were analysed by sensitive immunoassays. The study included 379 non-allergic and allergic subjects. The genotype prevalence of the EPX/EDN405(G>C) polymorphism was GG 59%, GC 36% and CC 6%. The cellular contents of ECP and EPX/EDN were related in a reciprocal fashion with the sums of the protein contents being constant. The contents were associated with the ECP562(G>C) rs2233860 and EPX/EDN405(G>C) gene polymorphisms. The cellular content of eosinophil peroxidase (EPO) was not associated with the ECP and EPX/EDN genotypes. The prevalence of the EPX/EDN405(G>C) genotypes and the contents of the proteins were similar in non-allergic and allergic subjects.The production and storage of the two ancestral proteins, ECP and EPX/EDN likely share common regulatory mechanisms, which result in opposing productions of the two proteins.

Association between inflammatory biomarkers and in-stent restenosis tissue features: an Optical Coherence Tomography Study

AIMS

Inflammatory reaction after stent implantation is associated with in-stent restenosis (ISR). We assessed the association of optical coherence tomography (OCT) features of neointima with systemic levels of high-sensitivity C-reactive protein (hs-CRP) and eosinophil cationic protein (ECP) measured at the time of ISR detection.

METHODS AND RESULTS

Patients presenting with symptomatic angiographically documented ISR (diameter stenosis ≥ 50% by visual estimation) were included. Quantitative OCT analysis included the measurement of minimal lumen diameter, minimal luminal area, stent and neointimal area, stent and restenosis length, restenotic tissue burden, and symmetry ratio. Qualitative OCT analysis included the assessment of ISR plaque type, neointimal tissue structure, lumen shape, presence of microvessels and calcific nodules. At the time of ISR detection hs-CRP and ECP levels were measured, and statistical analysis was performed using as cut-off 3 mg/L and 4.5 µg/L, respectively. Our population included 40 patients, 24 bare metal stents and 16 drug-eluting stents. Patients with high hs-CRP levels had a higher restenostic tissue symmetry ratio (0.56 ± 0.17 vs. 0.42 ± 0.13, P = 0.01) when compared with patients with low hs-CRP levels. Patients with high ECP levels had a higher neointimal burden (70 ± 14 vs. 64 ± 11, P = 0.05) in comparison with patients with low ECP levels.

CONCLUSIONS

Inflammatory biomarkers assessed at the time of ISR detection are associated with different aspects of neointimal tissue. While hs-CRP seems to have a role in neointimal tissue shape, ECP is related to a neointimal burden.

Systematic review of montelukast's efficacy for preventing post-bronchiolitis wheezing

Infants often develop reactive airway diseases subsequent to respiratory syncytial virus (RSV) bronchiolitis. Cysteinyl leukotrienes (cysLTs), a class of lipid mediators that have been implicated in the pathogenesis of allergic rhinitis and asthma, are released during RSV infection, thereby contributing to the pathogenic changes in airway inflammation. Many pediatric patients, especially those of very young age, continue to have recurrent episodes of lower airway obstruction after bronchiolitis treatment. This study was to systematically review and assessed the efficacy of montelukast for preventing wheezing in patients with post-bronchiolitis. The Cochrane library, PubMed, China National Knowledge Infrastructure (CNKI) periodical databases were screened for studies related to use of montelukast for preventing post-bronchiolitis wheezing published up to 31 December 2012. Randomized controlled trials (RCTs) and quasi-RCTs using montelukast alone as an active intervention in infants up to 24 months of age with post-bronchiolitis were selected. Two authors independently extracted data and assessed trial quality using the recommendations published by the Cochrane Collaboration. The meta-analyses were performed using the Cochrane statistical package RevMan5.0.0. Four trials, containing 1430 infants with confirmed diagnosis of acute bronchiolitis, were analyzed. Patients were administered montelukast at post-bronchiolitis. Three trials showed no effects of montelukast on reducing the incidence of recurrent wheezing risk ratios (RR = 0.78, 95% CI: 0.55-1.12, p = 0.17), while two trials found that montelukast did reduce the frequency of recurrent wheezing and another two trials demonstrated no effects of montelukast on symptom-free days. The pooled montelukast treatment group showed no significant effect on reducing the usage of corticosteroids, as compared to the placebo group (RR = 1.11, 95% CI: 0.85-1.44, p = 0.45). Two trials showed that montelukast significantly decreased serum eosinophil-derived neurotoxin levels, as compared to the control group. In general, the side effects of rash, vomiting, and insomnia caused by montelukast occurred in 1.5% of patients analyzed. The recent evidences indicate that montelukast may reduce the frequency of post-bronchiolitic wheezing without causing significant side effects but that it has no effects on decreasing incidences of recurrent wheezing, symptom-free days, or the associated usage of corticosteroid in post-bronchiolitis patients. The small number of enrolled participants and the inability to pool all clinical outcomes precludes us from making solid recommendations.

Which biomarkers are effective for identifying Th2-driven inflammation in asthma?

Recognition of asthma as a heterogeneous disease revealed different potential molecular targets and urged the development of targeted, customized treatment modalities. Evidence was provided for different inflammatory subsets of asthma and more recently, further refined to T helper (Th)2-high and Th2-low subphenotypes with different responsiveness to standard and targeted pharmacotherapy. Given these differences in immunology and pathophysiology, proof of concept studies of novel treatment modalities for asthma should be performed in adequate, well-defined phenotypes. In this review, we describe both existing and novel biomarkers of Th2-inflammation in asthma that can be applied to classify asthma subphenotypes in clinical studies and for treatment monitoring.

Pediatric asthma evaluation: what's to be considered?

The increasing evidence that asthma begins very early in childhood leads the need for having outcome's measures able to identify the early damage and its evolution both for research than for clinical purposes. The current available methods are clinical questionnaires, pulmonary function tests, airway reactivity tests and direct or indirect inflammation markers' measures. Among the first, ISAAC questionnaire, for epidemiological purpose, Asthma Control Test, for clinical monitoring and Health Related Quality of Life questionnaire are the most used. There are many pulmonary function tests that may be used in all age for functional evaluation, but airway responsiveness measures may be commonly performed only in school age children. As regards respiratory inflammation measures the only currently useful is the exhaled nitric oxide evaluation. The complexity of the pathogenic mechanisms, molecular, cellular and inflammatory that realize the asthmatic syndrome and the effects of the disease on respiratory function, on the activity of the child, on the quality of life of the family and on the economic costs to society show that there is no a single outcome measure that can evaluate all these effects simultaneously.

Serum biomarkers in elderly asthma

OBJECTIVE

Asthma is usually misdiagnosed and under-treated in the elderly population, resulting in complications and increased severity to the patient. In this review, we describe some of the most important serum markers of asthma studied so far, reporting their outcomes and possible prediction of asthma in the elderly population.

METHODS

The PubMed electronic database was used to search for promising serum biomarkers of asthma studied in original articles published in peer-reviewed journals from 2000 to January 2013.

RESULTS

A total of 13 relevant serum biomarkers were selected, including IgE, CRP, high sensitive CRP, IL-6, IL-8, IL-17, TNF-α, neopterin, serum amyloid A, eosinophil cationic protein, leukolysin, YKL-40 and soluble CD86.

CONCLUSIONS

Although the major focus of treatment and research has been on allergic asthma, several forms of the disease are recognized, such as neutrophilic asthma, which is characteristic of older patients. Different phenotypes imply different treatments and so it becomes important to correctly determine which type of asthma the patient is suffering from. Serum markers capable of supporting a diagnosis of asthma are needed in order to counter mistreatment and misdiagnosis with other obstructive airways disease (OAD) in elderly patients. As convenient as serum markers may seem to be, a marker capable of accurately identifying asthma with sufficient specificity is yet to be found.

Eosinophil-derived neurotoxin levels at 3 months post-respiratory syncytial virus bronchiolitis are a predictive biomarker of recurrent wheezing

OBJECTIVE

To determine whether eosinophil-derived neurotoxin (EDN) is a predictive marker of recurrent wheezing episodes in post-respiratory syncytial virus (RSV) bronchiolitis.

METHODS

EDN levels and recurrent wheezing episodes were serially measured in 200 infants hospitalized with RSV bronchiolitis.

RESULTS

Serum EDN levels at 3 months correlated significantly with total wheezing episodes at 12 months in the RSV-PLC (n  = 71; r = 0.720, p < 0.0001) and RSV-MONT groups (n = 79; r = 0.531, p < 0.001). Positive predictive value of 3-mo EDN level for total wheezing episodes was 57%; negative predictive value, 76%; sensitivity, 72%; specificity, 62%.

CONCLUSION

EDN levels have predictive value for the development of recurrent wheezing post-RSV bronchiolitis.

Eosinophil-derived neurotoxin: a novel biomarker for diagnosis and monitoring of asthma

Asthma is associated with increased levels of eosinophils in tissues, body fluids, and bone marrow. Elevated levels of eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP) have been noted in asthma patients. Higher levels of EDN and ECP are also associated with exacerbated asthmatic conditions. Thus, EDN, along with ECP, may aid the diagnosis and monitoring of asthma. Several groups have suggested that EDN is more useful than ECP in evaluating disease severity. This may partially be because of the recoverability of EDN (not sticky, 100% recovery rate), as ECP is a sticky and more highly charged protein. In terms of clinical utility, EDN level is a more accurate biomarker than ECP when analyzing the underlying pathophysiology of asthma. As a monitoring tool, EDN has shown good results in children with asthma as well as other allergic diseases. In children too young to fully participate in lung function tests, EDN levels may be useful as an alter native measurement of eosinophilic inflammation. EDN can also be used in adult patients and in multiple specimen types (e.g., serum, sputum, bronchoalveolar lavage fluid, and nasal lavage fluid). These results are repeatable and reproducible. In conclusion, EDN may be a novel biomarker for the diagnosis, treatment, and monitoring of asthma/allergic disease.

Salt chamber treatment is ineffective in treating eosinophilic inflammation in asthma

BACKGROUND

We have shown that salt chamber treatment reduces airway hyper-responsiveness as an add-on therapy in adult asthmatics on inhaled corticosteroids.

METHODS

We assessed whether this effect is due to the suppression of eosinophilic airway inflammation. Thirty-nine adult asthmatics on inhaled corticosteroids were randomized to receive active salt chamber treatment with low-salt treatment 6.6 mg/m(3) (n = 14), high-salt treatment 10.8 mg/m(3) (n = 15) or placebo 0.3 mg/m(3) (n = 10) 10 times in a 2 weeks' period in a double-blind manner.

RESULTS

The level of induced sputum eosinophilic cationic protein μg/l, was 3070 before and 4651 after the low-salt treatment period, on average. In the high-salt treatment group, it was 12 192 μg/l vs 11 803 and in the placebo group 3942 vs 4144, respectively. Salt chamber treatment had no effect on sputum eosinophil or neutrophil cell numbers.

CONCLUSIONS

The reduction in hyper-responsiveness observed in the previous study is probably not due to the effect on eosinophilic inflammation.

Onset of mucosal, dermal, and general symptoms in relation to biomarkers and exposures in the dwelling: a cohort study from 1992 to 2002

We examined the associations between biomarkers of allergy and inflammation, indoor environment in dwellings, and incidence and remission of symptoms included in the sick building syndrome (SBS) and changes in the home environment of 452 adults who were followed from 1992 to 2002 within the Uppsala part of the European Community Respiratory Health Survey (ECRHS). The 10-year incidence (onset) of general, mucosal, and dermal symptoms was 8.5%, 12.7%, and 6.8%, respectively. Dampness or indoor molds at baseline was a predictor of incidence of general (relative risk [RR] = 1.98), mucosal (RR = 2.28), and dermal symptoms (RR = 1.91). Women had higher incidence of general (RR = 1.74) and mucosal symptoms (RR = 1.71). Indoor painting increased the incidence of general symptoms (RR = 1.62). Bronchial responsiveness (BR), eosinophil counts in blood, total IgE and eosinophilic cationic protein (ECP) in serum at baseline were predictors of incidence of SBS. At follow-up, BR, total IgE, and C-reactive protein (CRP ) were associated with increased incidence of SBS. Moreover, subjects with doctor-diagnosed asthma at baseline had a higher incidence of general (RR = 1.65) and mucosal symptoms (RR = 1.97). In conclusion, female gender, dampness or indoor molds, indoor painting, and biomarkers of allergy and inflammation were associated with a higher incidence of SBS symptoms, in particular mucosal symptoms.

PRACTICAL IMPLICATIONS

The focus in Sweden on indoor environment issues over the last few decades has resulted in improvements in dwellings, and reduced tobacco smoking, which could be beneficial for public health. Reducing dampness and molds in the dwelling place is another important way of reducing occurrence of SBS symptoms in the general adult population. The association between the incidence of SBS symptoms and clinical biomarkers of allergy and inflammation suggests a common etiology between inflammatory diseases, including asthma, rhinitis, and SBS. Lastly, good agreement between self-reported and clinically diagnosed atopy indicates that questionnaire data on atopy can be used in epidemiological studies.

PI3-kinase regulates eosinophil and neutrophil degranulation in patients with allergic rhinitis and allergic asthma irrespective of allergen challenge model

The PI3K pathway plays a major role in many vital cell processes. Our primary aim was to investigate signalling through PI3K for in vitro degranulation from allergen-primed eosinophils and neutrophils in allergic rhinitis and allergic asthma after seasonal and experimental allergen challenge. Nine patients with allergic rhinitis, eight with allergic asthma and four controls were studied during birch pollen season and after nasal and bronchial allergen challenge. Primed blood eosinophils and neutrophils were stimulated for in vitro degranulation with C3b-coated Sephadex particles, after prior incubation with Wortmannin, a PI3K inhibitor. The released amounts of eosinophil cationic protein (ECP), eosinophil peroxidase (EPO) and myeloperoxidase (MPO) were measured by radioimmunoassay. Wortmannin (10(-6) to 10(-9) M) inhibited ECP, EPO and MPO release in a dose-dependent manner in allergic rhinitis and allergic asthma in all three allergen challenge models. Inhibition of ECP release tended to be lower in the asthmatics in all allergen challenge models, statistically significant compared to the controls during season for 10(-8) M Wortmannin (p=0.01). A clear propensity towards less inhibition in the rhinitic patients was seen after nasal and bronchial challenge compared to seasonal exposure, significant for ECP (10(-8) M Wortmannin; p=0.034 and 0.002, respectively). Signalling through PI3K is clearly involved in ECP, EPO and MPO release in allergic rhinitis and allergic asthma irrespective of allergen challenge model. Allergic asthma demonstrated less inhibition of ECP release via PI3K during pollen season, indicating that other pathways play a greater role in eosinophil degranulation in allergic asthma than allergic rhinitis.

Role of serological markers of activated eosinophils in inflammatory bowel diseases

BACKGROUND

Activated eosinophils can infiltrate the intestinal mucosa in patients with inflammatory bowel disease (IBD), and eosinophils are also implicated in the histological damage seen in allergic diseases.

AIM

To assess, in a group of patients with IBD in remission or with a mild disease activity, whether serological markers of eosinophil activation, eosinophil cationic protein (ECP) and eosinophil protein X (EPX), are related to evidence of IgE hypersensitivity and to the eosinophilia in gut mucosa.

METHODS

Sixty-one patients with IBD (21 Crohn's disease and 40 ulcerative colitis) in remission or with a mild disease activity were screened for IgE hypersensitivity and serological levels of ECP and EPX. Colonic biopsies were taken to assess mucosal eosinophilic infiltration.

RESULTS

Skin prick test were positive in 31.1% of the patients with IBD, showing skin reactions to food allergens in 17.7%. Skin prick test findings were unrelated to ECP or EPX levels, or to clinical activity or eosinophil counts in the gut mucosa. A significant correlation was found between ECP and EPX levels (r=0.77; P<0.0001).

CONCLUSION

Serological ECP and EPX findings did not correlate with IgE hypersensitivity findings or eosinophilic colonic infiltration in patients with IBD in remission or with mild disease activity. The role of eosinophils in IBD needs to be better characterized in the colonic mucosa, instead of relying on serological tests.

Infection, eosinophilia and childhood asthma

There is a growing list of viruses and bacteria associated with wheezing illness and asthma. It is well known that a few of these pathogens are strongly associated with wheezing illness and asthma exacerbations. What is not known is if early childhood infections with these pathogens cause asthma, and, if so, exactly what are the pathophysiologic mechanisms behind its development. The current consensus is respiratory infection works together with allergy to produce the immune and physiologic conditions necessary for asthma diasthesis. One link between respiratory infection and asthma may be the eosinophil, a cell that plays prominently in asthma and allergy, but can also be found in the body in response to infection. In turn, the eosinophil and its associated products may be novel therapeutic targets, or at the very least used to elucidate the complex pathophysiologic pathways of asthma and other respiratory illnesses. Together or separately, they can also be used for diagnosis, treatment and monitoring. The optimal care of a patient must take into consideration not only symptoms, but also the underlying disease mechanisms.

Measures of asthma control

PURPOSE OF REVIEW

Over the past decade, the concept of asthma control as distinct from asthma severity has been clearly defined. Well controlled asthma is the goal of therapy in all asthma patients. This review is a comprehensive description of the tools currently available for a methodical assessment of different aspects of asthma control in clinical practice and research.

RECENT FINDINGS

Several questionnaires for assessing asthma control have been extensively validated in adults. In children, validation data are less extensive. Considerable overlap exists between asthma control measures and measures of asthma-specific quality of life. Asthma-specific quality-of-life questionnaires have been used as primary outcome measures in major clinical trials evaluating asthma therapy. Biomarkers that reflect eosinophilic inflammation of the airways are used as intermediate outcome measures to reflect the biological basis of asthma control. There is some controversy, however, over which biomarkers are best incorporated into therapeutic algorithms that attempt to achieve maximal asthma control while minimizing treatment intensity.

SUMMARY

In designing clinical studies to evaluate different asthma therapies, researchers will find this review to be a useful resource in terms of choosing the appropriate tool for assessing asthma control. This is also a valuable resource for a methodical assessment of response to asthma therapy in routine clinical care.