The placenta plays a critical role in maternal-fetal nutrient transport and fetal protection against drugs. Creating physiological in vitro models to study these processes is crucial, but technically challenging. This study introduces an efficient cell model that mimics the human placental barrier using co-cultures of primary trophoblasts and primary human umbilical vein endothelial cells (HUVEC) on a Transwell®-based system. Monolayer formation was examined over 7 days by determining transepithelial electrical resistance (TEER), permeability of Lucifer yellow (LY) and inulin, localization of transport proteins at the trophoblast membrane (immunofluorescence), and syncytialization markers (RT-qPCR/ELISA). We analysed diffusion-based (caffeine/antipyrine) and transport-based (leucine/Rhodamine-123) processes to study the transfer of physiologically relevant compounds. The latter relies on the adequate localization and function of the amino-acid transporter LAT1 and the drug transporter P-glycoprotein (P-gp) which were studied by immunofluorescence microscopy and application of respective inhibitors (2-Amino-2-norbornanecarboxylic acid (BCH) for LAT1; cyclosporine-A for P-gp). The formation of functional monolayer(s) was confirmed by increasing TEER values, low LY transfer rates, minimal inulin leakage, and appropriate expression/release of syncytialization markers. These results were supported by microscopic monitoring of monolayer formation. LAT1 was identified on the apical and basal sides of the trophoblast monolayer, while P-gp was apically localized. Transport assays confirmed the inhibition of LAT1 by BCH, reducing both intracellular leucine levels and leucine transport to the basal compartment. Inhibiting P-gp with cyclosporine-A increased intracellular Rhodamine-123 concentrations. Our in vitro model mimics key aspects of the human placental barrier. It represents a powerful tool to study nutrient and drug transport mechanisms across the placenta, assisting in evaluating safer pregnancy therapies.

• Klíčová slova
• LAT1, P‐gp, co‐culture, endothelial cell, placental barrier, polarized monolayer, primary trophoblast, transport,
• MeSH
• biologické modely MeSH
• biologický transport MeSH
• endoteliální buňky pupečníkové žíly (lidské) * metabolismus   MeSH
• inulin metabolismus   MeSH
• isochinoliny MeSH
• kokultivační techniky MeSH
• leucin metabolismus   MeSH
• lidé MeSH
• maternofetální výměna látek * MeSH
• P-glykoprotein metabolismus   MeSH
• placenta * metabolismus   MeSH
• rhodamin 123 metabolismus   MeSH
• těhotenství MeSH
• trofoblasty * metabolismus   MeSH
• Check Tag
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• inulin MeSH
• isochinoliny MeSH
• leucin MeSH
• lucifer yellow MeSH Prohlížeč
• P-glykoprotein MeSH
• rhodamin 123 MeSH