Evaluation of optimal trophoblastic models to mimic uterine vessel remodeling in human pregnancy†.

During human pregnancy, a certain proportion of endothelial cells in uterine spiral arteries are replaced by placental extravillous trophoblasts (EVTs). This process is a pivotal step in spiral artery remodeling (SAR), ensuring the adequate supply of oxygen and nutrients to the fetus. Given the ethical constraints and the lack of suitable in vivo animal models, developing ideal in vitro models is crucial for investigating this cellular event. Therefore, it is imperative to evaluate key trophoblastic properties to optimize the in vitro model and replicate the in vivo context of SAR. In this study, we refined a three-dimensional co-culture system involving human trophoblast cells and tubular structure formed by human umbilical vein endothelial cells (HUVECs), allowing for dynamical monitoring of cell behaviors. Using this model, we conducted a comparative analysis of vascular remodeling capabilities among primary EVTs and various trophoblast cell lines. Meanwhile, we examined the expression profiles of multiple SAR-associated genes in trophoblast cells. The correlation between molecular characteristics and vascular remodeling performance was statistically analyzed using a comprehensive scoring system. Our findings highlight the critical roles of EVT-derived NCAM1, ITGB3, ITGAV, and JAG1 in vascular remodeling. Furthermore, JEG-3 and human trophoblast stem cell (hTSC)-derived EVT cells demonstrate significant advantages as optimal models for mimicking primary EVTs in vitro, thereby facilitating investigations into SAR. Consequently, we propose an evaluation framework to assess key attributes of trophoblast cell lines that enable them to accurately represent EVT behaviors in SAR. This study establishes a robust foundation for future exploration of the molecular mechanisms underlying human SAR.