We have succeeded in developing a co-culture of H295R human adrenocortical carcinoma cells with characteristics of the fetal adrenal and BeWo human choriocarcinoma cells with characteristics of the villous trophoblast that exhibits the steroidogenic functionality of the human fetoplacental unit.
Consistent with the functional steroidogenic fetoplacental unit during human pregnancy, our co-culture model is capable of progesterone, androgen, and estrogen biosynthesis de novo (Figure 1).
In the fetoplacental unit, CYP19 is mainly regulated via the PKC pathway through the major placental I.
A relevant in vitro steroidogenic model of the fetoplacental unit requires the de novo production of estrogens, including the pregnancy-specific hormone estriol, which is an indicator of fetal well-being (Mucci et al.
Despite the induction by atrazine of CYP19 activity in H295R cells (the fetal compartment), estradiol and estriol production by the co-culture (the cooperative fetoplacental unit) was not altered, indicating that the contribution of "fetal" CYP19 to overall estrogen production is small, if not negligible, in our co-culture model, as it is in the human fetoplacental unit in vivo.