Generation of Bona Fide Human Induced Trophoblast Stem Cells from Term Umbilical Cord

Placentation disorders such as severe fetal growth restriction and preeclampsia have their origin in the first trimester of pregnancy, whereas symptoms typically present later on. To be able to study the pathogenesis of these diseases, there is a need for a reliable model system of early placenta development with known pregnancy outcomes. Therefore, we aimed to optimize the generation of human induced trophoblast stem cells (iTSCs) from term umbilical cord using a direct reprogramming approach. In this, we added three supplements—A-485 (CREBBP/EP300 inhibitor), BMP4 or EPZ-6438 (PRC2 inhibitor)—that could potentially boost iTSC induction. The generated iTSCs fulfilled the criteria for bona fide first-trimester trophoblasts and exhibited transcriptional similarity to TSCs derived from first-trimester placental tissue, while the supplements tested did not substantially enhance iTSC induction. Overall design: Mesenchymal stem cells were isolated from a term umbilical cord, and transduced with the OSKM reprogramming factors. Seven days post-transduction, reprogramming intermediates were transited into human TSC medium to induce TSC conversion, with or without supplementation of A-485, BMP4 or EPZ-6438 for 1-3 days. Transcriptome sequencing was performed to assess the similarity between the generated iTSCs and TSCs derived from first-trimester placental tissue. The dataset contains 1-3 experimental replicates of each iTSC condition, 3 TSC lines, and TSCs differentiated into extravillous trophoblast for reference.