Strong inhibitory effect of pre-eclampsia serum on angiogenesis detected in vitro by human cell-based angiogenesis tests.

Abstract

To explore in vitro angiogenic properties of maternal and umbilical cord blood sera from women with symptomatic pre-eclampsia in comparison with sera from women with normotensive pregnancies. Maternal and umbilical blood serum samples were collected from eleven primiparous women with pre-eclampsia and ten healthy gestational-age-matched primiparous controls. The samples were tested for tubule formation in two different types of in vitro angiogenesis tests. The first test (fibroblast-HUVEC) showed effects on angiogenesis and the second test (hASC-HUVEC), in addition to angiogenesis, also showed effects on vasculogenesis. The pro-angiogenic and inhibitory properties of the samples were microscopically quantified after immunostaining tubular structures, using markers for von Willebrand factor (vWf) and collagen IV. Serum samples from pre-eclamptic women inhibited tubule formation in both models, while those from normal pregnancy didn't. Umbilical blood samples were inhibitory both after pre-eclampsia and normal pregnancy. In the fibroblast-HUVEC model the inhibition was stronger after preeclampsia pregnancy, and the difference between groups was statistically significant. In the pre-eclampsia group a correlation between the inhibitory effect of umbilical blood and birth weight adjusted to gestational age was found. No clear correlation between sera from pregnant women and corresponding umbilical sera was found. The strong inhibitory effect of maternal serum samples on tubule formation reflects the anti-angiogenic state that is present in pre-eclampsia.