A sensitive assay for anti-phosphatidylethanol-amine antibody in patients with recurrent fetal loss

There is strong evidence that anti-phospholipid antibodies is implicated in thrombosis and recurrent fetal death. In recent years, it has been suggested that anti-phosphatidylethanolamine (PE) antibody is an important antibody of this type. In the present study, we established a sensitive enzyme linked immunosorbent assay (ELISA) to detect anti-PE antibodies and examined the relationship between the anti-PE antibody level in serum and recurrent abortion. The improvement of the assay was made by treating PE with 1.0% acetic acid in methanol solution prior to its application to the microplates. This treatment markedly increased the antigenicity of PE. Using this modified ELISA, anti-PE antibodies in 10 patients with a history of recurrent fetal loss were measured before and after therapy during the last period of their pregnancies. IgG anti-PE antibodies were detected in all 10 patients. Four patients exhibiting high titers of IgG anti-PE antibody experienced subsequent intrauterine fetal death (IUFD), while the other 6 patients, whose titers of IgG anti-PE antibody had decreased with therapy, had live births. These results suggest that this modified ELISA for estimating IgG anti-PE antibody is a valuable tool for the diagnosis and prognosis of patients with recurrent fetal loss.