Background

Hazards of traffic-related air pollution (TRAP) on the developing immune system are poorly understood. We sought to investigate the effects of prenatal exposure to TRAP on cord blood immune cell distributions; and to identify gestational windows of susceptibility.

Methods

In-depth immunophenotyping of cord blood leukocyte and lymphocyte subsets was performed by flow cytometry in 190 newborns embedded in the Nutrition in Early Life and Asthma (NELA) birth cohort (2015-2018). Long-term (whole pregnancy and trimesters) and short-term (15-days before delivery) residential exposures to traffic-related nitrogen dioxide (NO₂), particulate matter (PM_2.5 and PM₁₀), and ozone (O₃) were estimated using dispersion/chemical transport modelling. Associations between TRAP concentrations and cord blood immune cell counts were assessed using multivariate Poisson regression models.

Results

Mean number of natural killer (NK) cells decreased 15% in relation to higher NO₂ concentrations (≥36.4 μg/m3) during whole pregnancy (incidence relative risk (IRR), 0.85; 95% CI, 0.72, 0.99), with stronger associations in the first trimester. Higher PM_2.5 concentrations (≥13.3 μg/m³) during whole pregnancy associated with a reduced mean number of cytotoxic T cells (IRR, 0.88; 95% CI, 0.78, 0.99). Newborns exposed to higher PM₁₀ (≥23.6 μg/m³) and PM_2.5 concentrations during the first and third trimester showed greater mean number of helper T type 1 (Th1) cells (P<0.05). Decreased number of regulatory T (Treg) cells was associated with greater short-term NO₂ (IRR, 0.90; 95% CI, 0.80, 1.01) and PM₁₀ (IRR, 0.88; 95% CI, 0.77, 0.99) concentrations.

Conclusions

Prenatal exposure to TRAP, particularly in early and late gestation, impairs fetal immune system development through disturbances in cord blood leukocyte and lymphocyte distributions.

中文翻译：

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怀孕期间交通造成的空气污染会损害新生儿的脐带血免疫细胞：NELA 队列

背景

交通相关空气污染 (TRAP) 对发育中的免疫系统的危害知之甚少。我们试图研究产前暴露于 TRAP 对脐带血免疫细胞分布的影响；并确定易感性妊娠窗口。

方法

通过流式细胞术对早年营养和哮喘 (NELA) 出生队列 (2015-2018) 中的 190 名新生儿进行脐带血白细胞和淋巴细胞亚群的深入免疫表型分析。长期（整个孕期和孕期）和短期（分娩前 15 天）住宅暴露于交通相关的二氧化氮 (NO ₂ )、颗粒物 (PM _2.5和 PM ₁₀ ) 和臭氧 (O ₃ )使用分散/化学传输模型估计。使用多变量泊松回归模型评估了 TRAP 浓度和脐带血免疫细胞计数之间的关联。

结果

在整个妊娠期间，自然杀伤 (NK) 细胞的平均数量与较高的 NO ₂浓度 (≥36.4 μg/m3) 相比减少了 15%（发生率相对风险 (IRR)，0.85；95% CI，0.72，0.99），具有更强的协会在第一个三个月。整个妊娠期间较高的 PM _2.5浓度（≥13.3 μg/m ³）与细胞毒性 T 细胞的平均数量减少相关（IRR，0.88；95% CI，0.78，0.99）。在孕早期和孕晚期暴露于较高 PM ₁₀ (≥23.6 μg/m ³ ) 和 PM _2.5浓度的新生儿显示出更多的辅助 T 型 1 (Th1) 细胞的平均数量 (P<0.05)。调节性 T (Treg) 细胞数量减少与短期 NO _{2增加有关}(IRR, 0.90; 95% CI, 0.80, 1.01) 和 PM ₁₀ (IRR, 0.88; 95% CI, 0.77, 0.99) 浓度。

结论

产前暴露于 TRAP，特别是在妊娠早期和晚期，会通过脐带血白细胞和淋巴细胞分布的紊乱损害胎儿免疫系统的发育。