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Background: It is currently discussed whether allergic sensitization may start in utero under the influence of the maternal immune system and environmental determinants. Objective: To investigate the relationship between allergen-specific cord blood (CB) IgE levels, parental sensitization, CB cytokine production, and environmental influences. Methods: As part of an ongoing multicenter birth cohort study, allergen-specific IgE antibodies against 20 common seasonal, perennial, and food allergens were measured in blood samples from 922 neonates, 922 mothers, and 835 fathers. Supernatants from stimulated CB cells were assessed for the production of IL-5, IFN-γ, IL-10, and TNF-α. Results: Allergen-specific IgE antibodies were detectable in 23.9% of newborns. Contamination with maternal serum was excluded by several means of analyses, including the absence of IgA antibodies. Clear correlation between maternal and fetal IgE was found only for hen''s egg, cow''s milk, and soybean allergen. Fetal IgE correlated negatively with the level of IFN-γ production, but not with IL-5 and IL-10. Conclusion: Allergen-specific IgE antibodies most probably of fetal origin are detectable in CB and correlate with a lowered CB IFN-γ production. [Copyright &y& Elsevier]

Background: Allergic bronchial asthma is a chronic inflammatory disease of the airways. The transcription factor GATA-3 was shown to play an important role in TH2 cell activation, but also in the regulation of other cell types involved in bronchial asthma including mast cells, eosinophils, and epithelial cells. DNAzymes represent a new class of antisense molecules that combines the specificity of DNA base pairing with an inherent RNA-cleaving enzymatic activity. Objective: To develop a GATA-3 mRNA-specific DNAzyme and analyze its allergy-preventing activity in murine models of experimental allergic asthma. Methods: The most active DNAzyme (termed gd21) was selected by in vitro cleavage assays. Allergic airway inflammation was assessed by inflammatory cell and cytokine analysis within bronchoalveolar lavage. Lung histology, including goblet cell hyperplasia and lung function, was analyzed using head-out body-plethysmography. Results: Intranasal administration of gd21 prevented airway inflammation and mucus production and inhibited development of airway hyperresponsiveness to methacholine in models of acute allergic airway inflammation. Similar effects were also detected in a model of chronic experimental asthma. Interestingly, gd21 was at least as effective as other antisense molecules, and off-target effects were not detected. Further experiments indicated that pulmonary surfactant may facilitate the cellular uptake of gd21 by acting as an endogenous transfectant. Conclusion: These results indicate that topical application of the GATA-3–specific DNAzyme is a promising novel approach for the treatment of allergic bronchial asthma. [Copyright &y& Elsevier]