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Air pollution exposure during critical time periods in gestation and alterations in cord blood lymphocyte distribution: a cohort of livebirths.

Herr CE, Dostal M, Ghosh R, Ashwood P, Lipsett M, Pinkerton KE, Sram R, Hertz-Picciotto I - Environ Health (2010)

Bottom Line: Data on covariates were obtained from medical records and questionnaires.In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions.Associations appear to differ by exposure in early versus late gestation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Public Health Sciences, University of California, Davis, USA.

ABSTRACT

Background: Toxic exposures have been shown to influence maturation of the immune system during gestation. This study investigates the association between cord blood lymphocyte proportions and maternal exposure to air pollution during each gestational month.

Methods: Cord blood was analyzed using a FACSort flow cytometer to determine proportions of T lymphocytes (CD3+ cells and their subsets, CD4+ and CD8+), B lymphocytes (CD19+) and natural killer (NK) cells. Ambient air concentrations of 12 polycyclic aromatic hydrocarbons (PAH) and particulate matter < 2.5 micrometer in diameter (PM2.5) were measured using fixed site monitors. Arithmetic means of these pollutants, calculated for each gestational month, were used as exposure metrics. Data on covariates were obtained from medical records and questionnaires. Multivariable linear regression models were fitted to estimate associations between monthly PAH or PM2.5 and cord blood lymphocytes, adjusting for year of birth and district of residence and, in further models, gestational season and number of prior live births.

Results: The adjusted models show significant associations between PAHs or PM2.5 during early gestation and increases in CD3+ and CD4+ lymphocytes percentages and decreases in CD19+ and NK cell percentages in cord blood. In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions. There was no significant association between alterations in lymphocyte distribution and air pollution exposure during the mid gestation.

Conclusions: PAHs and PM2.5 in ambient air may influence fetal immune development via shifts in cord blood lymphocytes distributions. Associations appear to differ by exposure in early versus late gestation.

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Related in: MedlinePlus

Associations between air pollutants and CD3+ lymphocyte fractions. Percent changes in cord blood lymphocyte distributions, with 95% CI, associated with average increases of 25 μg/m3 of PM2.5 by gestational month.
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Figure 4: Associations between air pollutants and CD3+ lymphocyte fractions. Percent changes in cord blood lymphocyte distributions, with 95% CI, associated with average increases of 25 μg/m3 of PM2.5 by gestational month.

Mentions: The relationship between PM2.5 and T lymphocytes was similar to that for PAHs: increased percentages of CD3+ and CD4+ cells when fine particulate exposures were higher in the first and second months of gestation, no association from months three through six and a lower percentage in months seven and nine. For instance, a 25 μg/m3 increase in PM2.5 exposure was associated with an increase in CD3+ cells by 2.5% (95% CI: 0.7, 4.2) in month one a decrease by 2.5% (95% CI: 0.9, 4.2) in month seven (Figure 4). The estimates were slightly smaller for CD4+ cells, a 2.2% (95% CI: 0.7, 3.7) increase for 25 μg/m3 increment in PM2.5 in month one and a 2.0% (95% CI: 0.6, 3.4) decrease in month seven (Figure 5). The only significant association with CD8+ cells was observed in month nine when there was a 0.7% (95% CI: 0.1, 1.3) decrease for a 25 μg/m3 increment in PM2.5 exposure (Figure 6).


Air pollution exposure during critical time periods in gestation and alterations in cord blood lymphocyte distribution: a cohort of livebirths.

Herr CE, Dostal M, Ghosh R, Ashwood P, Lipsett M, Pinkerton KE, Sram R, Hertz-Picciotto I - Environ Health (2010)

Associations between air pollutants and CD3+ lymphocyte fractions. Percent changes in cord blood lymphocyte distributions, with 95% CI, associated with average increases of 25 μg/m3 of PM2.5 by gestational month.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2927516&req=5

Figure 4: Associations between air pollutants and CD3+ lymphocyte fractions. Percent changes in cord blood lymphocyte distributions, with 95% CI, associated with average increases of 25 μg/m3 of PM2.5 by gestational month.
Mentions: The relationship between PM2.5 and T lymphocytes was similar to that for PAHs: increased percentages of CD3+ and CD4+ cells when fine particulate exposures were higher in the first and second months of gestation, no association from months three through six and a lower percentage in months seven and nine. For instance, a 25 μg/m3 increase in PM2.5 exposure was associated with an increase in CD3+ cells by 2.5% (95% CI: 0.7, 4.2) in month one a decrease by 2.5% (95% CI: 0.9, 4.2) in month seven (Figure 4). The estimates were slightly smaller for CD4+ cells, a 2.2% (95% CI: 0.7, 3.7) increase for 25 μg/m3 increment in PM2.5 in month one and a 2.0% (95% CI: 0.6, 3.4) decrease in month seven (Figure 5). The only significant association with CD8+ cells was observed in month nine when there was a 0.7% (95% CI: 0.1, 1.3) decrease for a 25 μg/m3 increment in PM2.5 exposure (Figure 6).

Bottom Line: Data on covariates were obtained from medical records and questionnaires.In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions.Associations appear to differ by exposure in early versus late gestation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Public Health Sciences, University of California, Davis, USA.

ABSTRACT

Background: Toxic exposures have been shown to influence maturation of the immune system during gestation. This study investigates the association between cord blood lymphocyte proportions and maternal exposure to air pollution during each gestational month.

Methods: Cord blood was analyzed using a FACSort flow cytometer to determine proportions of T lymphocytes (CD3+ cells and their subsets, CD4+ and CD8+), B lymphocytes (CD19+) and natural killer (NK) cells. Ambient air concentrations of 12 polycyclic aromatic hydrocarbons (PAH) and particulate matter < 2.5 micrometer in diameter (PM2.5) were measured using fixed site monitors. Arithmetic means of these pollutants, calculated for each gestational month, were used as exposure metrics. Data on covariates were obtained from medical records and questionnaires. Multivariable linear regression models were fitted to estimate associations between monthly PAH or PM2.5 and cord blood lymphocytes, adjusting for year of birth and district of residence and, in further models, gestational season and number of prior live births.

Results: The adjusted models show significant associations between PAHs or PM2.5 during early gestation and increases in CD3+ and CD4+ lymphocytes percentages and decreases in CD19+ and NK cell percentages in cord blood. In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions. There was no significant association between alterations in lymphocyte distribution and air pollution exposure during the mid gestation.

Conclusions: PAHs and PM2.5 in ambient air may influence fetal immune development via shifts in cord blood lymphocytes distributions. Associations appear to differ by exposure in early versus late gestation.

Show MeSH
Related in: MedlinePlus