To better explain how infections leading to birth defects cross from the mother to her unborn baby, researchers from the Magee-Womens Research Institute and the University of Pittsburgh developed a cell-based model for the human placenta, publishing their findings in the journal Science Advances.

According to senior investigator Carolyn Coyne, the placenta is a complex organ that not only anchors the developing baby to the uterus but also nourishes it and prevents the transfer of microorganisms if the mother is infected by forming a barrier.

With the development of the placental model, the researchers are hoping to further their knowledge of the organ, examining its functions and learning how the organ prevents many maternal infections from affecting a baby in the womb.

Other studies are focused on placental cell lines and primary human trophoblasts. The problem with the former, however, is that they don't spontaneously fuse to form an organ's characteristic structure, while the latter don't divide, are hard to obtain and difficult to manipulate genetically to uncover biochemical pathways responsible for placental function.

To address these concerns, Coyne and colleagues took another route, culturing a human placental trophoblast cell line using a microgravity bioreactor. They were able to mimic the maternal-fetal interface by adding trophoblasts and blood vessel cells to small dextran beads spun in cell culture fluid.

They were able to create syncytiotrophoblasts, which resemble primary cells lining the human placental tissues' outermost layer. The cells were then exposed to Toxoplasma gondii, a parasite in feline feces, and a virus that can lead to congenital diseases, miscarriages and/or disabilities later in life. Experimenting with various biological factors will let researchers determine which infectious agents are capable of bypassing the barrier created by the placenta and making their way to the fetus.

With a better understanding of the placenta, researchers may be able to one day prevent fetal damage from toxoplasmosis, cytomegalovirus, rubella, HIV and herpes.

For their next step, the researchers will be testing the Zika virus as well as other pathogens that have been associated with congenital diseases. Their work received funding support from the Burroughs Wellcome Fund and the National Institutes of Health.

Photo: Bridget Colla | Flickr