Pfefferle PI, Sel S, Ege MJ, et al; PASTURE Study Group. J Allergy Clin Immunol. 2008;122(4):711–716
PURPOSE OF THE STUDY. To investigate the relationship between allergen-specific cord blood (CB) immunoglobulin E (IgE) levels, parental allergen sensitization, CB cytokine production, and environmental influences.
STUDY POPULATION. This study included families recruited for the multicenter Protection Against Allergy–Study in Rural Environments (PASTURE) study, an ongoing longitudinal birth cohort study designed to evaluate risk factors and preventative factors for atopic disease. Pregnant women in their third trimester were recruited for participation from Finland, Germany, France, Switzerland, and Austria.
METHODS. CB samples were collected from umbilical cord veins, and parental blood samples were collected by peripheral vein puncture; the levels of allergen-specific IgE against 20 common inhalant and food allergens were measured by using the Allergy Screen (Mediwiss Analytic, Moers, Germany) test panel for atopy. The Allergy Screen result was compared with the skin-prick test result and showed a concordance of 92%. Serum IgA levels were determined by immunoturbidimetry. CB samples were stimulated by using astandardized protocol at local study centers, and cell-free supernatants were obtained by centrifugation for cytokine detection. Interleukin 5, interleukin 10, interferon γ (IFN-γ), and tumor necrosis factor α levels were measured with enzyme-linked immunosorbent assay techniques.
RESULTS. Allergen-specific IgE antibodies were detectable in 23.9% of the newborns. Paired IgE values from CB plus maternal blood and CB plus paternal blood were available for 922 and 835 children, respectively. Contamination with maternal serum was excluded by several means of analysis, including the absence of IgA antibodies. Concordance between CB IgE and maternal IgE against the same allergen was very low for inhalant allergens; in contrast, the concordance for various food allergens was considerably higher, particularly for hen's egg, cow's milk, and soybean. The percentages of IgE-negative mothers and fathers were equal for children who were sensitized to seasonal allergens (both 47%) but differed strongly for children who were sensitized to food allergens (21.9% [mothers] vs 65.7% [fathers]). There was an inverse association between CB IgE and the amount of CB IFN-γ (odds ratio: 0.69 [95% confidence interval: 0.58–0.83]).
CONCLUSIONS. Allergen-specific IgE antibodies, most probably of fetal origin, are detectable in CB and correlate with decreased CB IFN-γ production. This study revealed concordant IgE results between mother and child only for a few allergens; in IgE-positive mother-child pairs, the positive correlation was restricted to food allergens. If maternal contamination represented an important bias in the study, then such concordance would be expected throughout the entire spectrum of allergens tested.
REVIEWERS COMMENTS. The underlying mechanism and effect of IgE production in utero are still unclear. This study is important because it reports the presence of allergen-specific IgE antibodies in a considerably larger number of newborn infants than reported for previous studies. The results suggest that the capacity to produce IgE antibodies at this stage in life more likely depends on the suppression of the T-helper 1 compartment rather than an increase within the T-helper 2 cell effector subset. Of much interest would be the authors’ follow-up studies of this cohort, especially in terms of whether detection of allergen-specific IgE antibodies at birth is a transient phenomenon or is related to the development of allergic phenotypes.
- Copyright © 2009 by the American Academy of Pediatrics