Non-atopic asthma in children is related to maternal bronchial hyperreactivity.

Data on the pathogenic mechanisms underlying the development of non-atopic asthma in children are scarce. Our aim was to evaluate the association and compare the atopic status, pulmonary functions, bronchial hyperresponsiveness and serum total immunoglobulin E (IgE) levels of parents of atopic and non-atopic asthmatic children by using objective methods. Fifty-one asthmatic children aged 4-16 yr and their parents were included into the study. Initially the American Thoracic Society's Respiratory Disease questionnaire inquiring data on symptoms of asthma, rhinitis and past medical history was filled in. Afterwards, skin prick test with aeroallergens, pulmonary function and methacholine bronchial provocation tests and serum sampling for total IgE level determinations were carried out. Bronchial hyperresponsiveness to methacholine was significantly more common in the mothers of non-atopic children compared to those of atopic ones, although no significant difference was observed in the skin prick test reactivity, pulmonary function test parameters and serum IgE levels. Questionnaire data revealed that the presence of asthmatic symptoms such as wheezing and phlegm and doctor-diagnosed asthma were more common in the mothers of non-atopic children. Meanwhile, asthmatic symptoms were also found to be significantly more common in fathers of non-atopic children. Logistic regression analyses revealed that maternal PC(20) was the only predictive factor for the risk of displaying non-allergic asthma in children. The results demonstrate that among the risk factors studied, maternal bronchial hyperreactivity was associated with the development of asthma in non-atopic children.

Treatment with Mycobacterium vaccae ameliorates airway histopathology in a murine model of asthma.

The objective of this study was to evaluate the effect of intratracheal (i.t.) or subcutaneous (s.c.) Mycobacterium vaccae treatment on lung histopathology and cytokine responses in a murine model of asthma. BALB/c mice were divided into four groups. To establish an asthma model, Groups I, II and III received intraperitoneal (i.p.) ovalbumin (OVA) and were challenged with i.t. OVA three times (days 41-47). On the same days, mice in Groups I and II were treated with i.t. and s.c. Mycobacterium vaccae, respectively. Mice in Group IV served as controls. On day 49, lungs were taken out for histopathological evaluation. Cytokine levels were determined in splenocyte culture supernatants by ELISA. The thickness of basement membrane and hyperplasic goblet cells in small airways were found to be significantly more in Group III than Group I. Furthermore, smooth muscle and epithelial thickness in small and large airways and hyperplasic goblet cell numbers in all sized airways of this treatment group were not significantly different from controls. Epithelial thickness in medium and large airways, hyperplasic goblet cells in all sized airways, and basement membrane in small and large airways were not significantly different in Group II when compared to controls. OVA-stimulated IL-5 levels was significantly higher in Group I when compared to Group III. OVA-stimulated IL-5 and spontaneous IL-5 levels were significantly higher in Group II than Group III. We demonstrate that subcutaneous and intratracheal Mycobacterium vaccae administered along with allergen has an ameliorating effect in the modulation of airway histopathological changes in OVA sensitized mice.

Mycobacterium vaccae immunization to OVA sensitized pregnant BALB/c mice suppressed placental and postnatal IL-5 and inducing IFN-gamma secretion.

Although the development of atopy in the newborn is determined by a multitude of factors, an intense Th1 stimulus early in life could be protective by facilitating a switch away from Th2. Aimed to determine the effect of single Mycobacterium vaccae (M. vaccae) immunization to OVA-sensitized pregnant mice on IL-5 and IFN-gamma secretion from placental lymphocytes and splenocytes of offspring. Pregnant BALB/c mice were divided into 4 groups, OVA-sensitized + M. vaccae immunized, OVA-sensitized, M. vaccae immunized and controls. Sensitization with OVA was initiated before mating, and aerosol OVA challenge were performed during pregnancy. M. vaccae immunization was performed on the 12(th) day of pregnancy. IL-5 and IFN-gamma levels of placental lymphocytes were analyzed on the 18(th) day of pregnancy and splenocytes of offspring on the 2(nd) and 28(th) days during postnatal period. A single administration of M. vaccae to OVA-sensitized pregnant mice downregulated IL-5 secretion and induced IFN-gamma secretion from placental lymphocytes. On the other hand, after M. vaccae immunization downregulation of IL-5 levels and upregulation of IFN-gamma secretion persisted in offspring when determined on 2(nd) and 28(th) days of life. Vaccination with M. Vaccae to OVA-sensitized pregnant BALB/c mice prevented Th2 immune responses by enhancing secretion of IFN-gamma and lowering IL-5 levels during pregnancy and the effect persisted during the postnatal period in offspring.

Efficacy of long-term sublingual immunotherapy as an adjunct to pharmacotherapy in house dust mite-allergic children with asthma.

Although sublingual immunotherapy (SLIT) is accepted to be a viable alternative of specific-allergen immunotherapy, the efficacy of long-term SLIT in asthmatic children is not well established. The efficacy of 3 yr of SLIT in addition to pharmacotherapy was compared with pharmacotherapy alone in a prospective, open, parallel-group, controlled study. Children with asthma aged 4-16 yr, sensitive to house dust mite (HDM) were followed up for a run-in period of 1 yr and then grouped as those who would receive SLIT + pharmacotherapy (n = 62) or pharmacotherapy alone (n = 28). All patients were evaluated based on symptom-medication scores and lung function tests every 3 months, as well as skin-prick test and serum total immunoglobulin E (IgE) levels annually for 3 yr. Children in the SLIT + pharmacotherapy group demonstrated significantly lower mean daily dose and annual duration of inhaled corticosteroid (ICS) usage when compared with controls. At the end of the 3 yr, within-group comparisons revealed statistically significant decreases in the dose and duration of ICS only in the SLIT group. Furthermore, 52.4% of subjects in the SLIT + pharmacotherapy group were able to discontinue ICS treatment for at least 6 months, which was only 9.1% for the pharmacotherapy group. Three years of SLIT as an adjunct to pharmacotherapy resulted in reduction of both the duration and dose of ICSs and successful discontinuation of ICSs along with improvement in lung functions in HDM-allergic children with asthma.

Long-term modulatory effect of Mycobacterium vaccae treatment on histopathologic changes in a murine model of asthma.

BACKGROUND: Mycobacteria are being investigated for modulation of inflammation in asthma and atopic disorders by eliciting particularly strong protective TH1 immune responses. OBJECTIVE: To investigate the long-term effects of intratracheally administered Mycobacterium vaccae on an experimental murine model of asthma. METHODS: BALB/c mice were placed in 4 groups: long-term M. vaccae, M. vaccae, asthma, and control groups. All groups but controls were sensitized intraperitoneally and challenged intratracheally with ovalbumin. The long-term M. vaccae and M. vaccae groups were treated with M. vaccae intratracheally simultaneously during challenges. Finally, mice in the long-term M. vaccae group were rechallenged with ovalbumin nebulization 24 days later. Evaluations of lung histopathologic findings and serum cytokine levels were performed. RESULTS: Comparison of the long-term M. vaccae group with the asthma model group revealed that the number of hyperplasic goblet cells in small and large airways (small airway: P < .05; large airways: P < .01) and thickness of basement membrane in large airways were significantly less in the long-term M. vaccae group. Furthermore, numbers of hyperplasic goblet cells in small airways (P < .05) and basement membrane in the large airway (P < .05), as well as inflammation in small airways (P < .01), were significantly less in the M. vaccae group when compared with the asthma model group. Interferon-gamma secretion from splenocytes of the M. vaccae group was significantly higher than the asthma model and long-term M. vaccae groups. CONCLUSION: Intratracheal administration of M. vaccae exerted a long-lasting ameliorating effect on airway histopathologic features of a murine asthma model.

Association between previous enterobiasis and current wheezing: evaluation of 1018 children.

The aim of this study was to investigate the association between parasitosis and allergy. We surveyed all children aged 4-12 years living in poor hygienic conditions in a shantytown of Istanbul. After obtaining data from the International Study of Asthma and Allergies in Childhood (ISAAC) and an additional questionnaire, performing a skin-prick test (SPT), and determining total IgE, stool and perianal tape specimens were obtained from 1018 participating children. The prevalence of past episodes of wheezing, current wheezing, asthma, and rhinitis was 31, 14.6, 10.7, and 26.2%, respectively. Parasitosis was present in 49.1%, Enterobius vermicularis (23.3%), being the most common. A history of treatment for enterobiasis was present in 37%. Comparison of children with and without current enterobiasis revealed no significant difference in allergic manifestations and SPT results, except for serum total IgE level (p = 0.018), whereas children with previous enterobiasis were more likely to have current wheezing (p = 0.012). Current wheezers were more likely to have previous enterobiasis (p = 0.01) and a higher maternal employment level (p = 0.036) when compared with those without. According to logistic regression analysis, covariables significantly positively related with current wheezing were previous enterobiasis (p = 0.003) and being < or =5 years of age (p = 0.043), whereas being the first child of the family (p = 0.043) was negatively related. A previous infection with E. vermicularis was found to potentiate current wheezing in a population living in a shantytown in Istanbul.