Histopathologic and Transcriptomic Profiling Identifies Novel Trophoblast Defects in Patients With Preeclampsia and Maternal Vascular Malperfusion.

Preeclampsia (PE) is a heterogeneous disease for which the current clinical classification system is based on the presence or absence of specific clinical features. PE-associated placentas also show heterogeneous findings on pathologic examination, suggesting that further subclassification is possible. We combined clinical, pathologic, immunohistochemical, and transcriptomic profiling of placentas to develop integrated signatures for multiple subclasses of PE.

Modeling preeclampsia using human induced pluripotent stem cells.

Preeclampsia (PE) is a pregnancy-specific hypertensive disorder, affecting up to 10% of pregnancies worldwide. The primary etiology is considered to be abnormal development and function of placental cells called trophoblasts. We previously developed a two-step protocol for differentiation of human pluripotent stem cells, first into cytotrophoblast (CTB) progenitor-like cells, and then into both syncytiotrophoblast (STB)- and extravillous trophoblast (EVT)-like cells, and showed that it can model both normal and abnormal trophoblast differentiation.

High altitude regulates the expression of AMPK pathways in human placenta.

Introduction: High-altitude (>2500 m) residence augments the risk of intrauterine growth restriction (IUGR) and preeclampsia likely due, in part, to uteroplacental hypoperfusion. Previous genomic and transcriptomic studies in humans and functional studies in mice and humans suggest a role for AMP-activated protein kinase (AMPK) pathway in protecting against hypoxia-associated IUGR. AMPK is a metabolic sensor activated by hypoxia that is ubiquitously expressed in vascular beds and placenta.

Subclinical and clinical chorioamnionitis, fetal vasculitis, and risk for preterm birth: A cohort study.

Objective: To evaluate the association between subclinical and clinical chorioamnionitis and risk of preterm birth (PTB).

Methods: Demographic and clinical characteristics were abstracted from medical records and placental examinations performed (N = 1371 pregnancies including spontaneous and medically-indicated PTBs). Pregnancies were classified as having clinical chorioamnionitis (with or without histologic chorioamnionitis), subclinical chorioamnionitis (histologic, but not clinical, chorioamnionitis), or no chorioamnionitis; pregnancies with histologic chorioamnionitis were further evaluated for fetal vasculitis.

Comparative analysis of mouse and human placentae across gestation reveals species-specific regulators of placental development.

An increasing body of evidence points to significant spatio-temporal differences in early placental development between mouse and human, but a detailed comparison of placentae in these two species is missing. We set out to compare placentae from both species across gestation, with a focus on trophoblast progenitor markers. We found that CDX2 and ELF5, but not EOMES, are expressed in early post-implantation trophoblast subpopulations in both species.

Hypoxia Directs Human Extravillous Trophoblast Differentiation in a Hypoxia-Inducible Factor-Dependent Manner.

Villous cytotrophoblasts are epithelial stem cells of the early human placenta, able to differentiate either into syncytiotrophoblasts in floating chorionic villi or extravillous trophoblasts (EVTs) at the anchoring villi. The signaling pathways regulating differentiation into these two lineages are incompletely understood. The bulk of placental growth and development in the first trimester occurs under low oxygen tension.

Human pluripotent stem cells as a model of trophoblast differentiation in both normal development and disease.

Trophoblast is the primary epithelial cell type in the placenta, a transient organ required for proper fetal growth and development. Different trophoblast subtypes are responsible for gas/nutrient exchange (syncytiotrophoblasts, STBs) and invasion and maternal vascular remodeling (extravillous trophoblasts, EVTs). Studies of early human placental development are severely hampered by the lack of a representative trophoblast stem cell (TSC) model with the capacity for self-renewal and the ability to differentiate into both STBs and EVTs.

Maternal obesity and sex-specific differences in placental pathology.

Objective: Adverse effects of obesity have been linked to inflammation in various tissues, but studies on placental inflammation and obesity have demonstrated conflicting findings. We sought to investigate the influence of pregravid obesity and fetal sex on placental histopathology while controlling for diabetes and hypertension.

Methods: Placental histopathology focusing on inflammatory markers of a cohort of normal weight (BMI = 20-24.

MTA3 regulates differentiation of human cytotrophoblast stem cells.

Introduction: Early placental development depends on the correct balance of cytotrophoblast (CTB) proliferation and differentiation, into either syncytiotrophoblast (STB) involved in nutrient/gas exchange, or invasive extravillous trophoblast (EVT) involved in establishment of blood flow to the placenta. Metastasis associated protein-3 (MTA3) is a transcriptional co-repressor known to regulate cell migration. In addition, MTA3 is reportedly decreased in preeclampsia.