Figure 2.

Schematic of human placenta

View from tissues to cells.

(A) Representation of the fetus with umbilical cord and components.

(B) Detail of chorionic villi where the maternal blood vessels are invaded by trophoblasts, causing an immune response of macrophages, dendritic cells, and T lymphocytes. In the chorionic villus, there is an exchange of fetal cells, maternal cells, and DNA free cell.

(C) Detail of the cross-sectional anatomy of the chorionic villi and different cells layers and components. These structures allow the transfer of nutrients, gases, and waste substances between mother and fetus through the umbilical cord.