Trophoblast Stem Cell Markers
Human embryonic stem cells differentiate to form the three germ layers (ectoderm, mesoderm, and ectoderm) and the extra-embryonic tissue. Early differentiation results in two distinct populations. The inner cell mass (ICM) provides pluripotent cells that make up all the different cell types in the embryo. In addition, the trophectoderm develops into the trophoblast cell layers of the placenta. Metastasizing trophoblast cells are also responsible for mediating implantation of the embryo into the endometrium. Thus, trophoblast stem cells are used to model trophoectoderm differentiation and placental development in vitro. Research suggests that cultured trophoblast stem cells are dependent on FGF-4 signaling pathways.