Anti-HIV activity of a glycoprotein from first trimester placental tissue.

Human Immunodeficiency Virus-1 (HIV-1) transmission from a mother to the offspring during pregnancy is highly complex and a variable process in part due to the presence of several anti-HIV factors. In this study, we report an early pregnancy-associated protein (early pregnancy associated protein-1, Epap-1) with an apparent molecular weight of 90 kDa in placental tissue of pregnant women during the first trimester. Epap-1 was isolated and purified using Sambucus nigra agarose lectin affinity chromatography. Epap-1 strongly inhibits HIV-1(MN), HIV-1(91US056), HIV-1(VB-7) replication in vitro while it exhibits low activity with HIV-1(VB-66) strain. The molecular analysis of action of Epap-1 shows that it affects HIV-CD4 binding through inhibition of CD4-gp120 interaction.