Fig. 3: The overview of the schemes for the existing trophoblast fusion models.
From: A comprehensive review of human trophoblast fusion models: recent developments and challenges
Choriocarcinoma-derived cell lines, BeWo, JEG-3, and JAR, can be induced to fuse into syncytiotrophoblast (STB) and three-dimensional (3D) cell spheres using Forskolin in monolayer culture and 3D low adhesion culture, respectively. These trophoblast cell lines can also be co-cultured with other cell types on microfluidic devices to create placenta-on-a-chip. Placental explants can generate new STB through direct culture or “digestion-reconstruction” culture in vitro. Primary human trophoblasts (PHT) isolated from term placenta can spontaneously fuse to form STB in monolayer culture. Human trophoblast stem cells (TSCs) can now be obtained through the induction of various stem cells or specific trophoblast culture methods, including primed embryonic stem cells (ESCs), Naïve ESCs, villi cytotrophoblast cells (vCTBs), human candidate TSCs population (cTSCs), induced TSCs (iTSCs), induced PSCs (iPSCs), and expanded PSCs (ePSCs). These TSCs can then be induced to differentiate into STB through monolayer culture or form organoids or 3D cell spheres using a range of 3D cultures, including low adhesion culture, hanging culture, and low gravity culture.
