|Primary chorionic villi. Diagrammatic.|
|Secondary chorionic villi. Diagrammatic.|
|Gray's||subject #6 47|
The cytotrophoblast (or layer of Langhans) is the inner layer of the trophoblast, interior to the syncytiotrophoblast in an embryo. It serves to anchor the embryonic chorion to the maternal endometrium.
Cytotrophoblasts are stem cells in the chorionic villi. During differentiation, mononuclear cytotrophoblast fuse together into the multinucleated syncytiotrophoblasts.
These cells invade maternal uterine tissues and thus are in direct contact with maternal stroma and immune cells.
Section through embryonic area of Vespertilio murinus to show the formation of the amniotic cavity.
- Histology image: 19908loa – Histology Learning System at Boston University - "Female Reproductive System: placental villi"
- Diagram at McGill