22 research outputs found
Characterization of regulatory T cells in urban newborns
© 2009 Ly et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Vitamin D intake in mid-pregnancy and child allergic disease â a prospective study in 44,825 Danish mother-child pairs
Background: Past studies suggest that maternal vitamin D intake during pregnancy may protect against child wheeze but studies on asthma are limited. Our objective was to examine the relation between intake of vitamin D in mid-pregnancy and child asthma and allergic rhinitis at 18Â months and 7Â years. Methods: We examined data from 44,825 women enrolled during pregnancy in the longitudinal Danish National Birth Cohort (1996â2002). We estimated vitamin D intake from diet and supplements based on information from a validated food frequency questionnaire completed in gestational week 25. At 18Â months, we evaluated child asthma using data from phone interviews. We assessed asthma and allergic rhinitis by self-report at age 7 and asthma by using records from national registries. Current asthma at age 7 was defined as lifetime asthma diagnosis and wheeze in the past 12Â months. We calculated multivariable risk ratios with 95% CIs comparing highest vs. lowest quintile of vitamin D intake in relation to child allergic disease outcomes. Results: The median (5%-95%ile) intake of total vitamin D was 11.7(3.0-19.4) ÎŒg/day (68% from supplements). In multivariable analysis, mothers in the highest (vs. lowest) quintile of total vitamin D intake were less likely to have children classified with current asthma at 7Â years (Q5 vs. Q1: 0.74, 95% CI: 0.56, 0.96, Pâ=â0.02) and they were less likely to have children admitted to the hospital due to asthma (Q5 vs. Q1: 0.80, 95% CI: 0.64, 1.00, Pâ=â0.05). We found no associations with child asthma at 18Â months or with allergic rhinitis at 7Â years. Conclusions: Our findings suggest a weak inverse relationship between high total vitamin D and asthma outcomes in later, but not early, childhood. The data did not suggest a clear threshold of vitamin D intake above which risk of asthma was reduced
Lack of effect of benralizumab on signs and symptoms of moderateâtoâsevere atopic dermatitis: Results from the phase 2 randomized, doubleâblind, placeboâcontrolled HILLIER trial
Activation of naturally occurring lung CD4+CD25+ regulatory T cells requires CD8 and MHC I interaction
Naturally occurring Foxp3+CD4+CD25+ T cells (nTregs) isolated from lungs of naive mice regulate allergic airway hyperresponsiveness (AHR) and inflammation. Here, we demonstrate the critical requirement for engagement of MHC class I on CD4+CD25+ T cells by CD8 for the functional activation of these nTregs. Suppression of allergen-induced AHR and inflammation by nTregs was abolished in mice treated with anti-CD8. Correspondingly, decreased levels of IL-10 and TGF-ÎČ and increased levels of Th2 cytokines in bronchoalveolar lavage were detected in these treated mice. Similarly, nTregs isolated from ÎČ2mâ/â mice or from mice treated with anti-MHC I antibody in vitro before intratracheal transfer failed to modulate AHR or inflammation. Coculture of nTregs with CD8+ T cells increased IL-10 and TGF-ÎČ. Addition of anti-MHC I or anti-CD8 reduced IL-10 and TGF-ÎČ. These results demonstrate that functional activation of nTregs requires the interaction between MHC I on CD4+CD25+ T cells and CD8