Trophoblasts and soluble adhesion molecules in peripheral blood of women with pregnancy-induced hypertension

The current hypothesis on the pathogenesis of pregnancy-induced hypertension (PIH) considers it as an endothelial disorder that is first local but with the potential of becoming general. The aim of the work was to investigate the relation of the number of trophoblast cells in maternal peripheral blood against the serum levels of soluble vascular and intercellular cell adhesion molecule (sVCAM-1 and sICAM-1) in PIH.

Women with PIH were at 28th to 40th week of gestation. Control group were normotensive (NT) pregnant women at 28th to 41st week of gestation. Flow cytometry was used to assess the relative number of the trophoblasts in the peripheral blood. Trophoblasts were labeled with monoclonal anti-human trophoblast protein antibody MCA 277. The presence of sVCAM-1 and sICAM-1 was determined using the enzyme-linked immunosorbent assay method.

Women with PIH had significantly higher trophoblasts number than NT women (median 19.0, range 5.0-57.0/400 microL versus median 7.0, range 0.0-18.0/400 microL; P = 0.000011) as well as plasma level of sVCAM-1 when compared with NT women (median 730.0, range 325.0-1525.0 ng/mL versus median 493, range 310-1075 ng/mL; P = 0.02). ICAM-1 level in the PIH group was slightly elevated (median 280.0, range 174.0-524.0 ng/mL) when compared with NT women (median 260.0, range 190.0-464.0 ng/mL, P = 0.322). Eight of 21 women with PIH had proteinuria but no correlation was found between this symptom and the laboratory findings.

The increased number of trophoblast cells in maternal peripheral blood and higher levels of sVCAM-1 correlate with the presence of PIH. The differences of sVCAM levels were significantly higher than those observed for sICAM. The results indicate an association between circulating trophoblasts and vascular endothelium activation, during PIH.