Does the idea of printing an organ sound intriguing? Scientists have recently used a novel 3D printing technique to arrange human embryonic stem cells (hESCs) for the very first time. This could allow the creation of three-dimensional tissues and structures, which could be crucial in the making of artificial organs and tissues.

These hESCs are crucial when it comes to medical research. The cells can replicate indefinitely and can become almost any type of cell in the body. That makes them extremely useful when it comes to creating tissues that will not be rejected by a body.

Although 3D printing has been tested before, scientists have used inkjet technology with other types of cells, including adult stem cells. Before now, though, hESCs have been too delicate to use with the printing technology.

The findings, published in the journal Biofabrication, show off a new technique for printing with these fragile cells, though. The researchers from Heriot-Watt University in collaboration with Roslin Cellab, a stem cell technology company, used a valve-based printing technique tailored to account for the delicate properties of hESCs. The researchers loaded the hESCs into two separate reservoirs in the printer and then were deposited into a plate in a pre-programmed uniformed pattern.

In order to make sure that technique was successful, the scientists then performed a number of tests. They made sure that the hESCs remained alive after printing and tested to see if they maintained their ability to differentiate into different types of cells. In addition, they also checked to see if the concentration, characterization and distribution of the hESCs were accurate enough to make the valve-based printing method viable.

It turned out that this method wasn't only viable, but precise. The scientists found that the printed cells, driven by pneumatic pressure and controlled by the opening and closing of a microvalve, were in order and maintained their ability to be differentiated into any other cell type.

Currently, the method could be used to speed up and improve the process of drug testing. In the longer term, though, this printing method may pave the way for incorporating hESCs into artificially created organs and tissues ready for transplantation into patients suffering from a variety of diseases.