Cytokine profiles in cord blood in relation to prenatal traffic-related air pollution: The NELA cohort.

Abstract

Outdoor air pollution may disturb immune system development. We investigated whether gestational exposure to traffic-related air pollutants (TRAP) is associated with unstimulated cytokine profiles in newborns. Data come from 235 newborns of the NELA cohort. Innate response-related cytokines (IL-6, IFN-α, IL1-β, and TNF-α), Th1-related (IFN-γ and IL-2), Th2-related (IL-4, IL-5, and IL-13), Th17-related (IL-17 and IL-23), and immunomodulatory cytokine IL-10 were quantified in the supernatant of unstimulated whole umbilical cord blood cells after 7days of culture using the Luminex technology. Dispersion/chemical transport modeling was used to estimate long-term (whole pregnancy and trimesters) and short-term (15days before delivery) residential exposures to traffic-related nitrogen dioxide (NO2 ), particulate matter (PM2.5 and PM10 ), and ozone (O3 ). We fitted multivariable logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression models. NO2 during the whole pregnancy increased the odds of detection of IL-1β (OR per 10µg/m3 increase=1.37; 95% CI, 1.02, 1.85) and IL-6 (OR per 10µg/m3 increase=1.32; 95% CI 1.00, 1.75). Increased odds of detected concentrations of IL-10 was found in newborns exposed during whole pregnancy to higher levels of NO2 (OR per 10µg/m3 increase=1.30; 95% CI 0.99, 1.69), PM10 (OR per 10µg/m3 increase=1.49; 95% CI 0.95, 2.33), and PM2.5 (OR per 5µg/m3 increase=1.56; 95% CI 0.97, 2.51). Exposure to O3 during the whole pregnancy increased the odds of detected IL-13 (OR per 10µg/m3 increase=1.22; 95% CI 1.01, 1.49). WQS model revealed first and third trimesters of gestation as windows of higher susceptibility. Gestational exposure to TRAP may increase detection of pro-inflammatory, Th2-related, and T regulatory cytokines in newborns. These changes might influence immune system responses later in life.