Anti-phospholipid antibodies in preeclampsia and their binding ability for placental villous lipid fractions

Abstract

Objective: In order to investigate the significance of the anti-phospholipid antibodies (APAs) in preeclampsia, 3 kinds of APAs-namely, the anti-cardiolipin antibody (ACA), the anti-phosphatidylserine antibody (APSA), and the anti-phosphatidylcholine antibody (APCA)-were measured, and the APA-binding ability for placental villi using villous lipid fractions was studied.

Methods: Serum samples were taken from 70 cases of preeclampsia, including 42 cases of the severe type, and from 45 normal pregnant women. The APAs were measured by an enzyme linked immunoabsorbent assay (ELISA). Placental villous membranes (PVMs) from normal placenta were purified and the lipid fractions were extracted from PVMs. The antibody-binding ability for PVM lipid fractions was evaluated by the ELISA method.

Results: In IgG-antibody measurements, the rate of ACA-positive, APSA-positive and APCA-positive cases were 10.0%, 18.1%, and 7.1%, respectively. The presence of APAs was revealed in preeclampsia. Using thin-layer chromatography, negatively charged phospholipids were found in the lipid fractions obtained from PVMs. Antibody binding for the lipid fractions of PVMs was detected in 9 of 12 APA-positive cases in preeclampsia.

Conclusion: The results suggest that one cause of preeclampsia is the production of antiphospholipid antibodies that bind to placental villous membrane antigens.