See-through human organs and transparent creatures might sound like something from the lab of a mad scientist, but these incredible creations are not the playthings of Dr Frankenstein. Instead, they could help pave the way for 3D-bioprinted organs in the near future.

Neuroscientists at Ludwig Maximilians University in the German city of Munich have spent years working on a way to create transparent biological tissues through a process known as DIfferential Subsampling with Cartesian Ordering (DISCO).

As explained in a number of their studies, such as in the journal Nature Protocols in 2012 and Protocol Exchange in 2016, the technique uses organic solvents to "clear" the tissue and render them transparent. So far, researchers have used the method on a number of different tissues, from whole mice to human brains (image below).

By making them transparent, researchers are able to study the intricate anatomy and detailed structure of tissues from an unprecedented viewpoint. For example, scientists can carry out laser scanning of the entire transparent organ without having to slice it up and then use the imaging to gain new insights into its inner vascular structure.

Although other transparent tissue technologies have been developed, this particular technique was pioneered by Dr Ali Erturk, an artist and neuroscientist at Ludwig Maximilians University. Dr Erturk says the DISCO technique could pave the way for the 3D bioprinting of whole organs using cells and biological materials. As Reuters reports, Erturk and his team are even hoping to create a 3D-printed pancreas within the next 3 years and a kidney within 5 to 6 years.

“We can see where every single cell is located in transparent human organs. And then we can actually replicate exactly the same, using 3D bioprinting technology to make a real functional organ,” Erturk told Reuters.

“Therefore, I believe we are much closer to a real human organ for the first time now.”

Earlier this month, another team of scientists in Israel made an incredible breakthrough by 3D-printing a heart using a patient’s own cells. Although the organ is only small, about the size of a rabbit’s heart, it’s a stunning demonstration of how this exciting new technology holds a huge amount of promise.