ESPE Abstracts

Background: Glucocorticoids play an important role in the developing fetus; the most important of which is lung maturation by increasing surfactant production and release. Glucocorticoid receptor (GR) functioning changes throughout the fetal period, especially during the transition to extrauterine life. Given the importance of glucocorticoids in lung development and functioning, studying glucocorticoid sensitivity (GS) in this population would be helpful, especially in the preterm population, to determine optimal steroid treatment for better lung outcomes. Few groups have characterized the glucocorticoid receptor and its sensitivity using cord blood monocytes. Our pilot studies looking at term neonates born to mother without complications demonstrated that cord blood monocytes could be used as a non-invasive way to measure glucocorticoid sensitivity using a Fluorescein labelled dexamethasone (F-Dex) monocyte binding assay in this population.

Objective and hypotheses: We propose to use cord blood monocytes to characterize glucocorticoid sensitivity in preterm neonates using a Fluorescein labelled dexamethasone (F-Dex) monocyte binding assay. We also propose to determine what factors can effect GS in neonates.

Method: 25 cord samples were collected for neonates in the following cohorts: five from mothers with GDM, five from mothers with infection, five from mothers who smoke, five from mothers with pre-eclampsia and five from IUGR infants. We compared F-Dex binding in these groups to 25 term healthy neonates born without any complications that served as controls.

Results: Preliminary results so far show that the F-Dex binding in these cohorts were similar to that in the control neonate populations.

Conclusion: Our preliminary results show that factors such as gestational diabetes, maternal smoking, infection, pre-eclampsia and IUGR does not effect F-Dex binding in neonate cord blood monocytes. We will need to collect more sample to examine these factors and others further.