3D Printed Placenta Poised to Help Explain Organ Development

Pictures of organoid development from the study, showing the locations of different kinds of cells. Part of the reason the study was undertaken was to understand where different cells (Image courtesy of Haider et al, 2018.)

European researchers have 3D printed a simplified, organic model of the human placenta, and hope to use it for studying the organ’s development.

On August 2^nd, 2018 researchers at the Medical University of Vienna released a study detailing their creation of a placenta organoid. An organoid is a smaller, simplified, 3D version of an organ, 3Dprinted out of stem cells. The 3D shape is important; a cells’ development is shaped by connection and communication with neighboring cells, and so cells grown in 2D environments like petri dishes aren’t accurate models of cells in organs.

In recent years, organoids have become more popular as a method for researching how organs react and respond to different drugs. In fact, researchers at the Wake Forest Institute for Regenerative Medicine have even connected tiny heart, liver, and lung organoids into a “body on a chip” to test different drug interactions. But the study of placentas isn’t as well-developed as the study of other organs.

This study has several important firsts: it’s the first three-dimensional 3D-printed placenta, the first self-renewing 3D-printed placenta (which means that stem cells keep forming new tissue), and the first 3D-printed placenta to contain all three kinds of trophoblasts, the cells to make up the placenta.

“No organoid system for the human placenta was available before,” said Martin Knöfler, one of the researchers. “In the past, preparations of primary trophoblast cells didn’t survive longer than approximately one week.”

They started with first-trimester cytotrophoblasts: the cells that make up the inner wall of the placenta.

Development of the placental cells. (Image courtesy of Haider et al, 2018.)

The placenta organoid could be used for drug testing, to see what impacts a drug might have on pregnant women. “The fact that there were no self-renewing cell culture model systems available for the human placenta made it difficult, if not impossible, to study the causes of malfunctions,” said Knöfler. “Establishment of the placenta organoid system will improve this situation significantly and will help advancing drug development and consequently medical treatments for dangerous gestational disorders.”

But before they start testing drugs, the team wants to use their model to see how the placenta develops normally: “For the moment it is important to understand how the specific trophoblast subtypes, with their different roles, develop, and how failures in that developmental program contribute to pregnancy disorders.”