Anti-VEGF treatment suppresses remodeling factors and restores epithelial barrier function through the E-cadherin/ß-catenin signaling axis in experimental asthma models.

Besides maintaining a physical barrier with adherens junctional (AJ) and tight junctional proteins, airway epithelial cells have important roles in modulating the inflammatory processes of allergic asthma. E-cadherin and ß-catenin are the key AJ proteins that are involved in airway remodeling. Various mediators such as transforming growth factor-ß (TGF-ß), epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet derived growth factor (PDGF), insulin-like growth factor (IGF), tumor necrosis factor-α (TNF-α) and angiogenic factors, such as vascular endothelial growth factor (VEGF), are released by the airway epithelium in allergic asthma. The signaling pathways activated by these growth factors trigger epithelial-mesenchymal transition (EMT), which contributes to fibrosis and subsequent downregulation of E-cadherin. The present study used a mouse asthma model to investigate the effects of anti-VEGF, anti-TNF and corticosteroid therapies on growth factor and E-cadherin/ß-catenin expression. The study used 38 male BALB/c mice, divided into 5 groups. A chronic mouse asthma model was created by treating 4 of the groups with inhaled and intraperitoneal ovalbumin (n= 8 per group). Saline, anti-TNF-α (etanercept), anti-VEGF (bevacizumab) or a corticosteroid (dexamethasone) were applied to each group by intraperitoneal injection. No medication was administered to the control group (n=6). Immunohistochemistry for E-cadherin, ß-catenin and growth factors was performed on lung tissues and protein expression levels assessed using H-scores. Statistically significant differences were observed in E-cadherin, ß-catenin, EGF, FG, and PFGF (P<0.001 for all) as well as the IGF H-scores between the five groups (P<0.005). Only anti-VEGF treatment caused E-cadherin and ß-catenin levels to increase to the level of non-asthmatic control groups (P>0.005). All treatment groups had reduced TGF-ß, PDGF and FGF H-scores in comparison with the untreated asthma group (P=0.001). The EGF and IGF levels were not significantly different between the untreated asthmatic and non-asthmatic controls. The results suggested that anti-VEGF and TNF-α inhibition treatments are effective in decreasing growth factors, in a similar manner to conventional corticosteroid treatments. Anti-VEGF and TNF inhibition therapy may be an effective treatment for remodeling in asthma while offering an alternative therapeutic option to steroid protective agents. The data suggested that anti-VEGF treatment offered greater restoration of the epithelial barrier than both anti-TNF-α and corticosteroid treatment.

Clinical Usefulness of Acute-Phase Markers in Distinguishing between PFAPA and Other Exudative Tonsillitis Causes: A Methodological Study.

BACKGROUND: We investigated the practical use of procalcitonin (PCT), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and complete blood count (CBC) parameters in distinguishing periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis syndrome (PFAPA) attacks from exudative tonsillitis associated with group A streptococcus (GAS) and Epstein-Barre virus (EBV). METHODS: The study population consisted of cases with exudative tonsillitis who had been subsequently diagnosed as PFAPA, EBV, and GAS tonsillitis through a period of 6 years. We retrieved the CBC, ESR, CRP and PCT data from patients' medical records. RESULTS: Of the patients, 47 (35.6%) had PFAPA, 36 (27.3%) had GAS and 49 (37.1%) had EBV tonsillitis. Median CRP, ESR and PCT values of patients with PFAPA were 78 (17-92) mg/dl, 44 (11-83) mm/h, 0.16 (0.01-1.45) ng/ml, respectively. The CRP and ESR levels were significantly higher in PFAPA and GAS groups compared with the EBV group (p = 0.001). There was no significant difference between the groups regarding the PCT levels. CONCLUSION: The study indicated no benefit of PCT in distinguishing PFAPA from the others. However, we found that CRP, ESR, and CBC parameters could be useful in identifying PFAPA and GAS than EBV tonsillitis.

Significant Changes in Trans-Epithelial Barrier Proteins of Adenoid Tissue with Atopic Status in Children.

OBJECTIVES: Adenoid tissue is important in local immune response and epithelial barrier dysfunction of this tissue may contribute to allergies. The aim of this study was to evaluate the relationship between the status of cross-epithelial barrier elements in adenoid tissue lymphoepithelium and inhalant allergen sensitization. MATERIALS AND METHODS: Children aged 5-15 years, who underwent adenotonsillectomy, participated in this study. All subjects underwent skin prick testing with environmental inhalant allergens. Occludin, ZO1, e-cadherin, ß-catenin, desmoglein, desmoplakin, and connexon-43 were stained immunohistochemically in the adenoid tissues obtained and scored by H-score. RESULTS: We enrolled 76 children, 14 among whom were sensitized to environmental allergens. Among the zonula occludens proteins, median H-scores for occludin, claudin, and ZO-1 were significantly lower in the atopic compared to the nonatopic group respectively (p<0.001). Similarly, median H-scores for e-cadherin and ß catenin proteins of the zonula adherens were significantly lower in the atopic group (p<0.001). Both desmoglein and desmoplakin H-scores were significantly lower in the atopic group [60 (50-100) vs 280 (260-300), p<0.001 and 105 (87.5-120) vs 280 (67.25-300), p<0.001 respectively]. Moreover, connexin-43 protein of the gap junction was significantly lower in the atopic group (p<0.001). CONCLUSION: Adenoid tissue, which is the initial point of contact of inhalant allergens demonstrates epithelial barrier junctional protein, changes in children with inhalant allergen sensitization without clinical allergic disease symptoms. Therefore, it may be concluded that epithelial barrier function plays an important role in the development of allergen sensitization versus tolerance.

Safety of subcutaneous allergen immunotherapy in children: A retrospective review and bird eye to literature.

Toprak-Kanik E, Yilmaz Ö, Yangin-Ergon E, Türkeli A, Yüksel H. Safety of subcutaneous allergen immunotherapy in children: A retrospective review and bird eye to literature. Turk J Pediatr 2018; 60: 684-690. Subcutaneous allergen immunotherapy (SCIT) has been shown to improve clinical course in children with asthma and allergic rhinitis (AR). Systemic and local side-effects may be seen during its administration. The purpose of this study was to evaluate risk factors associated with systemic and local side-effects in children receiving SCIT. We performed a retrospective chart review in the children who received allergen subcutaneous immunotherapy for asthma and/or allergen rhinitis. Demographic data, diagnosis, skin prick test results, presence of additional allergic diseases, the seasonal variation of adverse events in the first and third years of SCIT were recorded. A total of 508 eligible patients were included in the study. Mean age of the children was 10.9±3.2 years, and 65.4% were male. Asthma was present in 21.9% of the children, AR in 44.7%, 33.5% of them had both asthma and AR. According to the skin prick test results, sensitivity to more than one allergen was present in 45.1%, while the most common single-allergen sensitivities were to grass pollen and dermatophagoids (32.5% and 14.4%, respectively). Ratio of systemic and local side-effects was 4.7% and 9.3%, respectively. Local side-effects were more common than systemic reaction. SCIT is a safe treatment modality while using the appropriate dose and with the administration of dose-escalation protocol.

Vascular endothelial growth factor antagonism restores epithelial barrier dysfunction via affecting zonula occludens proteins.

Epithelial barrier dysfunction is important in the pathogenesis of asthma and allergic responses, and is therefore a therapeutic target. The aim of the present study was to investigate the effects of dexamethasone, a classic therapeutic agent, an anti-tumor necrosis factor agent (etanercept), which is used to treat difficult cases of asthma, and an anti-vascular endothelial growth factor (VEGF) agent (bevacizumab), which is an angiogenesis inhibitor, on zonula occludens (ZO) proteins in an experimental asthma model. The experimental model of asthma was developed using intraperitoneal (IP) and inhaled administration of ovalbumin in 38 BALB/c mice, which were divided into four groups. The control group (n=6) did not receive any treatment, while the four remaining groups (n=8 per group) received an IP injection of saline, etanercept, bevacizumab or dexamethasone, respectively. Occludin, claudin and junctional adhesion molecule (JAM) were immunohistochemically stained in the left middle lobe samples using an indirect avidin-peroxidase method, after which the staining was semiquantified with H-scores. Statistically significant differences were observed in the occludin, claudin and JAM H-scores among the four groups (P<0.001). In the untreated asthma, etanercept, bevacizumab and dexamethasone groups, the median H-scores for occludin were 93, 177, 280 and 198, respectively, while the H-scores for claudin were 82, 193.5, 274 and 202.5, respectively, and the median H-scores for JAM were 130, 210, 288 and 210, respectively. Pairwise comparisons revealed that all three ZO protein H-scores were significantly lower in the saline group when compared with each treatment group. However, the H-scores of the ZO proteins were not significantly different between the etanercept and dexamethasone groups. Furthermore, the bevacizumab group exhibited higher H-scores for all the proteins compared with the dexamethasone group. Therefore, antagonism of VEGF with bevacizumab restores the epithelial barrier to a greater extent when compared with dexamethasone treatment. This result may be promising for the development of novel therapeutic agents.

IL-5, IL-8 and MMP -9 levels in exhaled breath condensate of atopic and nonatopic asthmatic children.

RATIONALE: Asthma is a heterogeneous disease, and a great majority of pediatric patients with asthma demonstrate atopic characteristics and develop a Th2 type cytokine response. Nonatopic asthma, on the other hand, is seen more rarely. METHODS: In this study, levels of IL-5, IL-8 and MMP-9 were measured in exhaled breath condensate (EBC) of the subjects to demonstrate the extent of tissue damage as well as eosinophilic and neutrophilic inflammation in children with atopic and nonatopic asthma. A total of 37 children with atopic asthma and 37 children with nonatopic asthma were enrolled in the study. Patients who exhibited protease positive aeroallergen (House dust mite, mould mix, olea, grass mix) sensitivity in allergen skin prick test were included in the atopic asthma group. To evaluate the EBC, the fluid content of the breath was collected by having the patients exhale into an EBC device, after which the IL-5, IL-8 and MMP-9 levels were assayed using the ELISA method. RESULTS: The atopic asthmatics exhibited significantly higher IL-5 levels in their EBC samples than the nonatopic asthmatics (0.271 [0.198-0.489] pg/ml and 0.198 [0.125-0.344] pg/ml, respectively, p = 0.04), while no significant differences were observed in the levels of IL-8 and MMP-9 in the EBC samples of the atopic and nonatopic asthmatics. CONCLUSIONS: IL-5 levels, as a marker of eosinophilic inflammation, were demonstrated to be higher in the children with atopic asthma when compared to those with nonatopic asthma in EBC. The fact that no significant difference was apparent in the IL-8 levels between the groups suggests that it is the severity of the disease rather than the atopic state that plays an important role in IL-8 levels. Since no difference was recorded between the groups in terms of MMP-9 levels, lung damage in asthma sufferers seems to develop independent of atopia.

E-cadherin as an epithelial barrier protein in exhaled breath condensate.

Airway epithelium plays an important role as a physical barrier and a modulator of allergic response. Junctions between cells provide epithelial integrity and barrier function. The aim of this study was to investigate the influence of atopy on airway epithelial integrity in asthma and to measure E-cadherin levels in exhaled breath condensate as an indicator epithelial damage. A total of 74 patients with asthma (35 atopic and 39 non-atopic) and 39 healthy children were enrolled in this case-control study. Sociodemographic characteristics and asthma severity parameters in the last three-month period were recorded and pulmonary function tests were performed. Blood samples were obtained to measure serum immunoglobulin E (IgE) levels and peripheral blood eosinophil count, and exhaled breath condensate (EBC) was obtained to measure E-cadherin.EBC E-cadherin levels were significantly lower in the asthmatics when compared to non-atopic controls (0.109 (0.076) versus 0.191 (0.184) ng mL(-1) respectively, p = 0.01). Atopic and non-atopic asthmatic groups had lower EBC E-cadherin levels compared to the control group. (0.112 (0.060) ng ml(-1), 0.106 (0.089) ng ml(-1) and 0.191 (0.184) ng ml(-1), p = 0.02 and p < 0.01 respectively). However, EBC E-cadherin levels were not different between atopic and non-atopic asthmatics. The results of our study support the role of E-cadherin in the pathogenesis of asthma. However, the absence of difference in E-cadherin levels between atopic and non-atopic asthmatics suggests that allergic sensitization is not the primary factor for development of epithelial barrier dysfunction in asthma.

Risk factors for candidemia in pediatric intensive care unit patients.

OBJECTIVE: To determine the risk factors for developing candida infections in pediatric intensive care unit (PICU). METHODS: The present study was conducted as a case-control study and included the population of patients who were admitted to PICU during the period of March 2010-March 2011. RESULTS: During the study period, a total of 57 patients in PICU had candidemia, 4 cases were excluded due to their PICU stay less than 48 h and one due to the insufficient data. The most commonly isolated Candida species was C. albicans, followed by C. parapsilosis. The median duration of hospitalization in PICU was higher (22.0 d) in candidemia patients compared to control group (13.5 d) (p = 0.037). The patients with candidemia had higher rates of presence of mechanical ventilation, presence of central venous catheter, and being under total parenteral nutrition; compared to the control group. CONCLUSIONS: The longer PICU durations, mechanical ventilation, central venous catheter, total parenteral nutrition were the associated factors. Although trials for predicitive models or scoring systems for development of candidemia have been performed; more future studies were required for practical usage in clinics settings in order to prevent candidemia.

Follicular bronchiolitis: a rare disease in children.

Follicular bronchiolitis (FB) is a benign progressive lung disease. It is characterized with lymphoplasmocellular infiltration and hyperplastic follicles in the peribronchial areas in the small airways. Follicular bronchiolitis should be considered in cases where chronic cough, recurrent upper respiratory tract infections and progressive dyspnea are observed in children. The diagnosis should be supported by lung biopsy. A 8-year old female patient presented to our hospital with complaints including continuing cough and wheezing. Bilateral extensive rales and rhonchi in the lungs were heard on auscultation and lung graphy revealed reticuloglandular appearance. Bilateral extensive septal thickennings, reticulonodular appearance, patchy bronchiectasis, bronchiolectasis and peribronchial thickennings were found on high-resolution thoracal computarized tomography. A diagnosis of follicular bronchiolitis was made as a result of lung biopsy. Improvement was observed in the complaints and findings of our patient after methylprednisolone treatment. This patient was presented to emphasize rare interstitial lung diseases should also be considered in children who present with a clinical picture of chronic bronchial obstruction and do not respond to standard treatment.

Assessment of myocardial dysfunction in neonates with hypoxic-ischemic encephalopathy: is it a significant predictor of mortality?

OBJECTIVES: Hypoxic-ischemic cerebral injury due to perinatal asphyxia is an important cause of neonatal mortality and morbidity. To predict who will survive or die due to this disorder still remains obscure. The aim of this study is to evaluate the predictive value of myocardial involvement in the assessment of mortality for the neonates with hypoxic-ischemic encephalopathy (HIE). PATIENTS AND METHODS: The study included 34 term newborns fulfilling the diagnostic criteria for HIE and staged according to Sarnat and Sarnat classification. To assess the myocardial involvement, electrocardiogram (ECG) and echocardiogram (Echo) were performed in the first 24-48 h of life. In addition, serum Troponin I and creatine kinase-myocardial band (CK-MB) were measured at delivery and postnatal day 3. RESULTS: Of the 34 cases, 19 (55.9%) were stage in 1, 9 were in (26.4%) stage 2 and 6 (17.6%) were in stage 3 HIE. Nine (26.4%) patients died of the disease. Thirteen patients (38.2%) showed ECG findings related to perinatal asphyxia. Only one patient had mild Echo changes. Higher Troponin I level was a significant predictor of mortality, whereas CK-MB did not show any significant predicting value. Troponin I test showed 33% sensitivity and 80% specificity in predicting mortality. In addition, the sensitivity and specificity of ECG as a predictor of mortality were 77 and 76%, respectively. CONCLUSION: This study highlights the significance of monitoring cardiac functions in newborns with HIE. ECG changes and serum Troponin I level at 72 h after birth are likely to have significant predictive value in the assessment of mortality in HIE. Further studies will provide additional data for the long-term prognostic value of cardiac functions in this disorder.