Lentiviral, Placental Giant Cell‐Specific Gene Targeting

Abstract

Pre-eclampsia and intrauterine growth restriction (IUGR) are pregnancy-related disorders that stem from abnormal placental development. Pre- eclampsia, a disorder involving shallow embryonic invasion, is also known as toxemia or pregnancy-induced hypertension (PIH), and occurs in 6-8% of all births in the United States. The placenta is composed of trophoblast cells that are organized into three layers: the giant cell layer, the spongiotrophoblast layer, and the labyrinthine layer. Previous studies have shown that oxygen is an important mediator of trophoblast differentiation. Hypoxia inducible factor-1 alpha (HIF-1a) is a critical component of the cellular oxygen-sensing machinery and is essential for placental formation and embryonic survival. Preliminary data indicates that prolonged activity of HIF-1a, restricted to trophoblast cells in the mouse placenta, results in changes to placental architecture, failure of trophoblasts to remodel the maternal arteries, premature birth, and low birth weight offspring. In order to address the role of hypoxia in the giant cell layer of the placenta, we created a lentiviral construct that is a cell-specific, trophoblast giant cell lineage promoter, mPL2. The first of the lentiviral constructs created for testing includes a green fluorescent protein (GFP) gene driven by mPL2 promoter. To subsequently test hypoxia, the green fluorescent protein gene will be replaced with the HIF-1a gene. This final construct will then be used in in-vivo embryo transfer studies to test oxygen sensing in the giant cell layer of the placenta and provide a better understanding of pre-eclampsia and intrauterine growth restriction.