3-D printing breakthrough with stem cells

Three-dimensional printing is all the rage: from crafting musical instruments and prosthetic limbs to constructing a manned base on the moon.

In the field of health, Heriot-Watt University in Edinburgh, in collaboration with Roslin Cellab, a Scottish stem cell technology company, are leading the way in developing 3-D stem cell printing for commercial uses.

In the latest breakthrough, published today in the journal Biofabrication, the team has succeeded in printing human embryonic stem cells (hESCs) for the first time. Many studies have experimented with fabricating 3-D tissues and organs by combining artificial solid structures and animal, not human, cells.

"The generation of 3-D structures from hESCs will allow us to create more accurate human tissue models which are essential for in-vitro drug development and toxicity testing," says study co-author Dr Will Wenmiao Shu, from Heriot-Watt. "Since the majority of drug discovery is targeting human disease, it makes sense to use human tissues."

In the longer term, this may also pave the way for incorporating hESCs into artificially created organs and tissues ready for transplantation into patients.

The hESCs are originally derived from an early-stage embryo to create "stem cell lines" which can be grown indefinitely and differentiate into any cell type in the body. Until now, these cell cultures had been too sensitive to manipulate by printing.

A valve-based printing technique was used, tailored to account for the sensitive properties of hESCs. Shu says: "We found that the valve-based printing is gentle enough to maintain high stem cell viability, accurate enough to produce spheroids of uniform size and, most importantly, the printed hESCs maintained their pluripotency - the ability to be differentiated into any other cell type."

Jason King, of Roslin Cellab, says: "This is a scientific development which we hope and believe will have immensely valuable long-term implications for reliable, animal-free drug-testing and, in the longer term, to provide organs for transplant on demand."