It is now well established that cells are exchanged between mother and fetus during
gestation. It has been proposed that some of these exchanges take place in the placenta,
but it has never been demonstrated. Here, we made use of EGFP (Enhanced Green
Fluorescent Protein) transgenic mice to precisely visualize the juxtaposition of maternal and
fetal tissues at the implantation site, as well as to describe the bi-directional cell trafficking
between mother and fetus at different stages of gestation. The influence of genetic …