IT’S ALIVE!? 3D Printing of Micro-Organs

3D printed structure shows promise for developing self-organizing tissues.

Printing functioning organs may still sound like science fiction, but a new process for creating embryoid bodies (EB) by 3D printing embryonic stem cells (ESC) could bring us another step closer to turning science fiction into science fact.

The printed cellular model with grid structure. (Image courtesy of Wei Sun)

The printed cellular model with grid structure. (Image courtesy of Wei Sun)

Researchers from Tsinghua and Drexel universities used an extrusion-based 3D printer to create three dimensional grids of ESCs embedded in hydrogel. These structures demonstrated cell viability and rapid self-renewal for seven days. During this time, the ESCs also maintained high pluripotency: the ability to change into various different cell types. 

Phase-contrast images of the printed cellular structure at day 3, day 5 and day 7. Scale bar: 1 mm. (Image courtesy of Wei Sun)

Phase-contrast images of the printed cellular structure at day 3, day 5 and day 7. Scale bar: 1 mm. (Image courtesy of Wei Sun)

“The grown embryoid body is uniform and homogenous, and serves as a much better starting point for further tissue growth [compared to 2D methods],” said Wei Sun, a professor at Drexel University and lead author of the article in Biofabrication. Their present goal is to develop their method to manufacture EB at a high-throughput, providing the building blocks for experiments on tissue regeneration or drug screening studies.

The 2D methods Sun is comparing to his 3D printing technique include common alternatives like printing two-dimensionally in a petri dish, or using the suspension method to build up a stalagmite of cells by dropping material.

Dr. Dan Thomas of Swansea University commented, “This research shows great promise towards the development of self-differentiated tissue structures. The test structures show a potential method for how to develop tissues that divide and organise themselves into complex living tissue.”

The research team’s long-term goal is to produce controlled heterogeneous EBs. “This would promote different cell types developing next to each other – which would lead the way for growing micro-organs from scratch within the lab,” said Rui Yao, another researcher on the project.

Additionally, this method could lead to the replacement of mice as laboratory proxies for humans, since micro-organs may do a better job of predicting human outcomes. They are also free from the ethical considerations associated with animal experimentation. 

Does the moral benefit of replacing mice with micro-organs justify expanding our use of embryonic stem cells? Tell us what you think in the comments section below.

For more information, view the researchers’ publication for free online.

Written by

Ian Wright

Ian is a senior editor at engineering.com, covering additive manufacturing and 3D printing, artificial intelligence, and advanced manufacturing. Ian holds bachelors and masters degrees in philosophy from McMaster University and spent six years pursuing a doctoral degree at York University before withdrawing in good standing.