The roles of a Th2 cytokine and CC chemokine in children with stable asthma: potential implication in eosinophil degranulation

Natural history of eosinophil‑derived neurotoxin levels and the onset of allergic airway disease in preschool children

'Atopic march' is the progression of allergic conditions through infancy and childhood. The present study investigated the association between blood eosinophil-derived neurotoxin (EDN) levels in preschool children with food allergy (FA) or atopic dermatitis (AD) and the onset of allergic airway disease [bronchial asthma (BA), allergic rhinitis (AR)]. A total of 123 children below the age of 1 year were enrolled in the present study, along with controls (n=37). Blood specimens were taken, serum EDN levels were measured and immunoglobulin E was quantified. Finally, a total of 86 subjects were analyzed. EDN values were measured at 3 time-points: before 1 year of age, before 2 years of age and before 3 years of age. The EDN levels were initially similar between those patients who did and those who did not develop allergic airway disease but then markedly diverged at the 2-year time-point (226.6 vs. 65.0 ng/ml; P<0.01) and remained divergent at the 3-year time-point (173.9 vs. 62.7 ng/ml; P<0.01). EDN levels prior to diagnosis were compared between the two groups and they were much higher in the Onset group (n=10) compared to the Non-onset group (n=67) (171.2±34.28 vs. 81.3±10.02 ng/ml; P=0.003), with 4 cases of BA and 6 cases of AR in the Onset group. After diagnosis, EDN levels were compared twice: i) At 1 and 2 years of age; and ii) 1 and 3 years of age. A significant difference was found only in the comparison at 2 years (P=0.001). In conclusion, young children with elevated EDN levels during the FA/AD disease period were more likely to develop allergic airway disease (BA, AR) in their first three years of life. A factor leading to this progression may be increased eosinophil activity.

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.

Association of RANTES gene polymorphisms with susceptibility to childhood asthma: A meta-analysis

BACKGROUND

Previous investigations have illustrated that regulated upon activation, normal T-cell expressed and secreted (RANTES) polymorphisms are linked to susceptibility to childhood asthma; nevertheless, the findings continue to be controversial. Accordingly, we conducted the present meta-analysis to clarify the impact of RANTES genetic polymorphisms (-403G/A and -28C/G) on childhood asthma vulnerability.

METHODS

A search for published literature was performed using the PubMed, EMBASE, Chinese National Infrastructure, Cochrane Library, Scopus, Web of Science, and WanFang databases and selected in the form of PICOS (participants, interventions, comparisons, outcomes, and study design) to identify all eligible research works. The link between RANTES genetic polymorphisms and childhood asthma susceptibility was evaluated by a pooled odds ratio with a 95% confidence interval.

RESULTS

In total, 14 case-control studies were included in the analysis. No significant association existed between risk of childhood asthma and the -403G/A polymorphism subjected to any genetic framework in the overall population. In the stratified analysis, according to ethnicity, the -403G/A polymorphism was linked to augmented vulnerability to childhood asthma in Caucasians (allelic model: odds ratio [OR] = 1.63, 95% confidence interval [CI] = 1.04-2.57, P = .034; codominant model: OR = 2.20, 95% CI = 1.28-3.78, P = .004; dominant model: OR = 1.78, 95% CI = 1.01-3.13, P = .047; and recessive model: OR = 1.92, 95% CI = 1.11-3.30, P = .019). For the stratified analysis by atopic status, the -403G/A polymorphism was linked to augmented childhood asthma in the codominant (OR = 1.39, 95% CI = 1.02-1.91, P = .037) and dominant models (OR = 1.43, 95% CI = 1.02-2.01, P = .037) in atopic asthma. For the -28C/G polymorphism, there was a significant association between childhood asthma and the -28C/G variant (allelic model: OR = 1.33, 95% CI = 1.08-1.65, P = .009; codominant framework: OR = 2.14, 95% CI = 1.47-3.10, P < .001; dominant model: OR = 1.44, 95% CI = 1.07-1.93, P = .017; and recessive model: OR = 2.08, 95% CI = 1.44-3.02, P < .001). Stratified analysis based on ethnicity and the -28C/G polymorphism was linked to augmented vulnerability to childhood asthma in Asian and Caucasian populations. For the subgroup analysis by atopic status, no association was found in atopic and non-atopic asthma.

CONCLUSION

The present meta-analysis indicated that the RANTES -403G/A and -28C/G polymorphisms contributed to the development of childhood asthma.

Relationship between chemokines and T lymphocytes in the context of respiratory allergies (Review)

Allergic diseases have been classified in the last decades using various theories. The main classes of the newest classification in allergic respiratory diseases focus on the characterization of the endotype (which takes into account biomarkers related to determinant pathophysiological mechanisms) and of the phenotype (based on the description of the disease). Th2, Th1 and Th17 lymphocytes and the type of inflammatory response mediated by them represent the basis for Th2 and non-Th2 endotype classification. In addition, new lymphocytes were also used to characterize allergic diseases: Th9 lymphocytes, Th22 lymphocytes, T follicular helper cells (T_FH) lymphocytes and invariant natural killer T (iNKT) lymphocytes. In the last decade, a growing body of evidence focused on chemokines, chemoattractant cytokines, which seems to have an important contribution to the pathogenesis of this pathology. This review presents the interactions between chemokines and Th lymphocytes in the context of Th2/non-Th2 endotype classification of respiratory allergies.

Severe bronchial asthma in children: a review of novel biomarkers used as predictors of the disease

Severe asthma or therapy-resistant asthma in children is a heterogeneous disease that affects all age-groups. Given its heterogeneity, precision in diagnosis and treatment has become imperative, in order to achieve better outcomes. If one is thus able to identify specific patient phenotypes and endotypes using the appropriate biomarkers, it will assist in providing the patient with more personalized and appropriate treatment. However, there appears to be a huge diagnostic gap in severe asthma, as there is no single test yet that accurately determines disease phenotype. In this paper, we review the published literature on some of these biomarkers and their possible role in bridging this diagnostic gap. We also highlight the cellular and molecular mechanisms involved in severe asthma, in order to show the basis for the novel biomarkers. Some markers useful for monitoring therapy and assessing airway remodeling in the disease are also discussed. A review of the literature was conducted with PubMed to gather baseline data on the subject. The literature search extended to articles published within the last 40 years. Although biomarkers specific to different severe asthma phenotypes have been identified, progress in their utility remains slow, because of several disease mechanisms, the variation of biomarkers at different levels of inflammation, changes in relying on one test over time (eg, from sputum eosinophilia to blood eosinophilia), and the degree of invasive tests required to collect biomarkers, which limits their applicability in clinical settings. In conclusion, several biomarkers remain useful in recognizing various asthma phenotypes. However, due to disease heterogeneity, identification and utilization of ideal and defined biomarkers in severe asthma are still inconclusive. The development of novel serum/sputum-based biomarker panels with enhanced sensitivity and specificity may lead to prompt diagnosis of the disease in the future.

Viral Infections and Associated Factors That Promote Acute Exacerbations of Asthma

Despite asthma being the most common chronic childhood ailment, there is still much to learn about the disease. Early childhood infections with well-known or emerging viruses can lay the pathophysiologic framework for asthma development and exacerbation later in life, which may be due partly to alteration of the airway microbiome. Once asthma is established, acute exacerbations are usually associated with infections with respiratory viruses, such as rhinoviruses (RVs). Once again, there are bidirectional interactions between viruses and airway bacteria that appear to influence the severity of illness and the likelihood of exacerbation. Studies employing recent advances in viral and bacterial identification analytic techniques will clarify these new concepts and may provide the basis for new treatments or prevention or respiratory infection-associated exacerbation. This paper is a review of the associations among respiratory viruses, bacteria, inflammatory mechanisms, and asthma exacerbation.

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.

Investigation of the anti‑asthmatic activity of Oridonin on a mouse model of asthma

Oridonin is an extract obtained from a traditional Chinese medicinal herb, Xihuangcao. Previous studies have demonstrated that Oridonin exerts various pharmaceutical effects, such as anti-tumor and immunosuppressive effects, as well as modulating cytokine balance. The present study identified that Oridonin could regulate the T_h1/T_h2 cytokine balance in mice. However, as the anti-asthmatic effect of Oridonin is currently unknown a mouse model of asthma was used in the present study. BALB/c mice were sensitized using ovalbumin (OVA), then the sensitized mice were treated with Oridonin prior to OVA challenge. The in vivo study indicated that Oridonin decreased the OVA-induced airway hyper-responsiveness significantly (P<0.05). In addition, the results indicated that in Oridonin-treated mice, the eosinophil number and total inflammatory cell number in bronchoalveolar lavage (BAL) fluid decreased significantly in the Oridonin group when compared with the control group. Further study indicated that Oridonin significantly decreased the level of inflammatory cytokines, which were induced by OVA, in BAL fluid. Histological studies were performed to evaluate the effect of Oridonin on eosinophilia and mucus in the airway, the results indicated that Oridonin significantly inhibited the eosinophilia and mucus production in the lungs. Therefore the present study demonstrated that Oridonin regulates T_h1/T_h2 balance in mice and exhibited anti-asthmatic effects in a mouse model of asthma. These findings indicate that Oridonin may serve as a potential therapeutic compound for the treatment of asthma in future.

Biomarkers and severe asthma: a critical appraisal

Severe asthma (SA) is a clinically and etiologically heterogeneous respiratory disease which affects among 5–10 % of asthmatic patients. Despite high-dose therapy, a large patients percentage is not fully controlled and has a poor quality of life. In this review, we describe the biomarkers actually known in scientific literature and used in clinical practice for SA assessment and management: neutrophils, eosinophils, periostin, fractional exhaled nitric oxide, exhaled breath condensate and galectins. Moreover, we give an overview on clinical and biological features characterizing severe asthma, paying special attention to the potential use of these ones as reliable markers. We finally underline the need to define different biomarkers panels to select patients affected by severe asthma for specific and personalized therapeutic approach.

Measuring eosinophiluria, urinary eosinophil cationic protein and urinary interleukin-5 in patients with Lupus Nephritis

BACKGROUND

Urine is increasingly becoming an attractive biological fluid in clinical practice due to being an easily obtained, non-invasive sampling method, containing proteins and peptides. The aim of this study was to investigate eosinophiluria, urinary eosinophil cationic protein (uECP) and urinary IL-5 (uIL-5) in patients with Lupus Nephritis.

METHODS

Seventy-four patients with SLE-20 with clinical and laboratory evidence of lupus nephritis (LN group) and 54 without evidence of renal involvement (non-LN group)-were analyzed regarding eosinophiluria, uECP and uIL-5. Eosinophiluria was observed by Hansel's stain, ECP by fluoroenzymeimmunoassay and uIL-5 by quantitative sandwich enzyme immunoassay. Both uECP and urinary IL-5 (uIL-5) were corrected by urinary creatinine. Eosinophiluria and uECP were compared with glomerular erythrocyturia, protein/creatinine ratio (Pr/Cr ratio), serum creatinine, estimated glomerular filtration rate (eGFR), anti-double-stranded DNA (anti-dsDNA), serum levels of complement (C3 and C4), uIL-5/Cr ratio, and SLE disease activity index.

RESULTS

Patients of the LN group had higher eosinophiluria, uECP, uECP/Cr ratio levels, and uIL-5 than patients of the non-LN group (p<0.001 for all). These variables showed a statistically significant correlation with glomerular erythrocyturia, casts, Pr/Cr ratio, serum creatinine, eGFR, anti-dsDNA, uIL-5/Cr, and SLE disease activity index (all p<0.05).

CONCLUSION

These results provide evidence of increased urinary eosinophils, ECP and IL-5 in patients with SLE and LN; uECP/Cr ratio showed better correlation with markers of renal function and SLE disease activity.

CCL11 as a potential diagnostic marker for asthma?

OBJECTIVE

Asthma is an inflammatory airway disease characterized by airway eosinophilia, in which CCL11 (eotaxin) plays a crucial role. The aim of study is to determine the elevation of CCL11 levels in bronchoalveolar lavage fluid (BALF), blood, exhaled breath condensate (EBC) and sputum in asthma patients and to identify which medium yields the most significant change in CCL11 level.

METHODS

The databases of PubMed, Embase and Cochrane Centre Register of Controlled Trials were systematically searched from inception to September 2013. Controlled clinical trials that focused on CCL11 concentrations in asthma patients and controls, and their correlations with other asthma indicators were obtained. Data were analysed using Stata 12.0.

RESULTS

Thirty studies were included in this investigation. CCL11 levels in blood, EBC and sputum were significantly higher in asthma patients than in healthy subjects. Sputum CCL11 concentrations were significantly elevated in unstable asthma patients versus stable asthma patients and in uncontrolled asthma patients versus partially controlled asthma patients. CCL11 levels in sputum and blood were negatively correlated with the lung function as measured by FEV1% predicted, and were positively correlated with BALF, EBC and sputum eosinophil counts. Similarly, CCL11 concentrations were positively correlated with eosinophil cationic protein in EBC, blood and sputum as well as with interleukin-5 in sputum and fractional exhaled nitric oxide in EBC. Steroid treatment had no significant effect on CCL11 levels.

CONCLUSIONS

CCL11 is a potentially useful biomarker for the diagnosis and assessment of asthma severity and control, especially in sputum. CCL11 is crucial in eosinophil chemoattraction and activation in asthma pathogenesis. Further studies using anti-CCL11 approaches are needed to confirm a role for CCL11 in asthma pathogenesis particularly in patients with more severe disease.

Detrimental effects of cement mortar and fly ash mortar on asthma progression

Currently, concrete additive materials are used worldwide to improve properties of concrete production and to reduce the total cost of the materials used in the concrete. However, the effects of exposure to various gases emitted from mortar mixed with additive materials are poorly understood. To evaluate the pattern of gas emission from cement mortar and additives, the emission levels of gas including ammonia (NH3) and volatile organic compounds (VOCs) were measured from two different mortar types, Ordinary Portland Cement (OPC), and OPC with fly ash on various time points after manufacture. On days 1, 3, 10 and 30 after manufacture, moderate concentrations of NH3 (4, 9, 12 and 5 ppm) were measured in OPC mortar (24h, 150 mm × 150 mm × 50 mm), whereas higher concentrations of NH3 (73, 55, 20 and 5 ppm) were measured in OPC mortar with fly ash (24h, 150 mm × 150 mm × 50 mm). Furthermore, the concentration of VOCs was more than 10 ppm on 1, 3, and 10 days of age in OPC and OPC with fly ash mortars. To examine the mortars' allergic effects on the respiratory system, mice were sensitized with ovalbumin (OVA) and divided into four groups: normal, asthma control, OPC mortar and OPC mortar with fly ash. The mice were housed in corresponding group cage for 10 days with OVA challenges to induce asthma. Histopathologically, increased infiltration of lymphocytes was observed in the lung perivascular area of mice housed in OPC mortar and OPC mortar with fly ash cages compared to lungs of asthma control mice. Moreover, severe bronchial lumen obstruction and increased hypertrophy of bronchial epithelial cells (p<0.05) were observed in the OPC mortar with fly ash group compared to OPC mortar or asthma control groups. Lungs of the two mortar groups generally expressed higher levels of genes related with asthma, including IL-4, eotaxin and epidermal growth factor (EGF) compared to lungs of asthma control mice. Additionally, the OPC mortar with fly ash group showed higher expression of IL-5, 13 and monocyte chemoattractant protein-1 (MCP-1) compared to the asthma control group. These results indicate that OPC mortar and OPC mortar with fly ash might exacerbate asthma.

Induced sputum cell count and cytokine profile in atopic and non-atopic children with asthma

BACKGROUND AND AIM

Sputum induction is a semi-invasive technique used to detect and monitor airway inflammation. In this study, the cell profile, and Th1 and Th2 cytokine levels in induced sputum of asthmatic and healthy children (HC) are compared.

METHODS

Sputum induction was performed in healthy and asthmatic children by inhalation of hypertonic saline solution. Differential cell count in the specimen obtained was carried out using optic microscopy. IFN-γ, IL-2, IL-10, IL-8, IL-6, IL-4, IL-5, IL-1β, TNF-α, and IL-12p70 levels were determined in sputum sample supernatants by flow cytometry.

RESULTS

Sputum induction was performed in 31 HC and 77 asthmatic children (60 atopic and 17 non-atopic asthma, NAA). Twenty-four samples were obtained in HC and 64 in patients. Median eosinophil count in atopic asthma (AA; 2%) was higher than in NAA (P = 0.02) or HC (P = 0.01). IL-4, IL-5, IFNγ, IL-2, and IL-12p70 concentrations were higher in AA than in NAA or HC. IL-8 was higher in asthmatic children (atopic and non-atopic) than in healthy ones. IL-10 was higher in the healthy group than in the AA group (P = 0.02).

CONCLUSIONS

As compared to HC, the inflammatory profile in induced sputum of children with asthma showed an increase in proinflammatory cytokines. Concentrations of IL-10, an anti-inflammatory cytokine, were lower in children with AA than in HC.

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.

Airway molecular phenotypes in pediatric asthma

PURPOSE OF REVIEW

The review discusses what is known regarding airway molecular phenotypes in pediatric asthma, specifically biomarkers that have been studied and their relation to the various clinical phenotypes of asthma.

RECENT FINDINGS

Pediatric asthma is a complex and heterogeneous disease that consists of several clinical phenotypes. There have been numerous studies investigating inflammatory markers that would increase our understanding of the underlying pathogenesis of asthma as well as facilitate the discovery of therapies for these patients. Some of these biomarkers, such as exhaled nitric oxide, exhaled breath condensate, urine leukotriene E4 and induced sputum are less invasive measures of inflammation than obtaining bronchoalveolar lavage fluid in children. Although recent data reveal that some of these measures may be helpful in classifying and managing pediatric asthma, further studies are critically needed before any of these biomarkers are able to be routinely used in clinical asthma care.

SUMMARY

The search for noninvasive biomarkers to help elucidate specific underlying molecular phenotypes in pediatric asthma should be a continued priority as we work towards improved care and management of these children.