Abstract
Background: The hygiene hypothesis suggests that the increasing prevalence of allergy in “westernised” countries is due to reduced bacterial exposure in early life, but the underlying mechanism remains elusive.
Objective: To analyse the effect of the bacterial product lipopolysaccharide (LPS) on the generation of regulatory T (TR) cells in neonates with allergy risk due to a family history of atopy (FH+) and in controls without such hereditary risk (FH−).
Methods: Cord blood mononuclear cells from the FH+ and FH- groups were stimulated with bovine â-lactoglobulin in an inherent LPS milieu. T-cell phenotypes indicative of TR cells (CD25+, CD25high and integrin áE+) and the proliferation antigen Ki-67 were quantified by flow cytometry. Release of TGF-â1 from its inactive complex was determined by ELISA.
Results: The FH+ group showed reduced capacity for generation of CD25+ T cells (FH+, 16.2% vs. FH−, 34.9%; p<0.01) and áE+ T cells (FH+, 2.1% vs. FH−, 3.9%; p<0.05). Moreover, the CD25high T cell subset tended to be impaired in the FH+ group (FH+, 5.1% vs. FH−, 12.6%). The frequency of proliferating T cells was inversely related to the CD25high phenotype (r=−0.54, p=0.05), and also to the activation-induced release of TGF-â1 (r=−0.80, p=0.001).
Conclusions: This study suggested that early-life exposure to a dietary antigen in physiological LPS milieu may generate TR cells, including the CD25high phenotype that was shown to be related to TGF-â activity and suppressed proliferation. This capacity was impaired in neonates with hereditary allergy risk, but clinical follow-up will be required to determine the effect on allergy emergence.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Haddeland, U., Brandtzaeg, P. & Nakstad, B. 198 Impairment of Putative Regulatory T Cells in Cord Blood From Neonates with Hereditary Allergy Risk. Pediatr Res 56, 497 (2004). https://doi.org/10.1203/00006450-200409000-00221
Issue Date:
DOI: https://doi.org/10.1203/00006450-200409000-00221