Plasma levels of α‐defensins 1–3 are an indicator of neutrophil activation in pregnant and post‐partum women

Abstract

In severe preeclampsia and septic shock, excessively activated neutrophils are thought to injure tissue irreversibly. On the other hand, mild neutrophil activation is known to occur during normal pregnancy. The objective of this study was to determine whether elevated plasma levels of alpha-defensins 1-3 could be used as an indicator of neutrophil activation in pregnant and post-partum women. Defensin concentrations in 21 non-pregnant women and men, 184 normal pregnant women, and 55 post-partum women were quantified using an enzyme-linked immunosorbent assay (ELISA). The expression of the surface markers, CD11b and Toll-like receptor-4 (TLR-4), on the neutrophils were analyzed by flow cytometry in a cohort of subjects different from that used for the analysis of alpha-defensin levels. The concentrations of alpha-defensins were significantly higher in women that were in labor than in any of the other subjects. These levels diminished after delivery, but remained significantly elevated at one month post-partum. The expression of both CD11b and TLR-4 was significantly higher in women in labor compared to non-pregnant donors (controls). CD11b expression remained high on the third post-partum day, while TLR-4 expression fell to non-pregnant levels. Our results suggest that there is a positive association between defensin levels and neutrophil activation in pregnant and post-partum women.