Allergen-specific T cell reactivity in cord blood: the influence of maternal cytokine production

Background Successful pregnancy is dependent upon T helper (Th)2-type-domin ated immunological responsiveness in gestation-associated compartments. Objective In our study we observed the influence of the maternal Th2-associ ated cytokine pattern on the naive fetal T cell phenotype and asked if circ ulating Th2 cytokines of atopic mothers affects the Th1/Th2 differentiation of the fetus. Methods Cord blood mononuclear cells (CBMC) and peripheral blood mononuclea r cells (PBMC) of the corresponding mothers were isolated. The proliferativ e response of CBMC and PBMC to Betalactoglobulin (BEG) was assessed by liqu id scintillation counting. The cytokines. interferon (IFN)-gamma, and inter leukin (IL)-5, IL-10 and IL-13 in the cell culture supernatants were measur ed using the ELISA technique. We then defined two subgroups based on matern al levels of specific IgE. against aeroallergens: sensitized mothers (MA(+) ) and their neonates (NMA(+)) (n = 18) and non-sensitized mothers (MA) and their neonates (NMA(-)) (n = 29). Results Nearly all mothers (98%) and neonates (92%) had a positive prolifer ation response after stimulation with BLG (mean stimulation index (10-90 pe rcentile): neonates: 7 (2-15); mothers 14 (5-29)). In supernatants of BLG-s timulated cell cultures, sensitized mothers showed a significantly lower IF N-gamma concentration in comparison to non-sensitized mothers (MA(+) = 25; MA(-) = 123 IU/L; P < 0,05), whereas the neonates did not differ significan tly (NMA(+) = 306; NMA- = 224 IU/L; n. s.). Nor was any difference found in the IL-13 concentration between the two groups of sensitized and non-sensi tized mothers (MA(+) = 48; MA(-) = 125 pg/mL; n. s.). CBMC of neonates with a sensitized mother showed significantly higher IL-13 concentrations in re sponse to BLG than neonates of nonsensitized mothers (NMA(+) = 1442, NMA(-) 738 pg/mL; P < 0.05). The IL-5 and IL-10 concentrations did not differ sig nificantly within the neonatal and the maternal subgroups. Conclusions Our data suggests that maternal sensitization to allergens is a ssociated with the reduced maternal production of the Th2 antagonist IFN-ga mma and elevated production of the Th2 cytokine IL-13 in the offspring.