Researchers develop breakthrough in 3D bioprinting blood networks with functioning skin.
The field of 3D bioprinting has shown great advancements toward the production of artificial organs that will work much like their biological counterparts. However, there has been one major hurdle: finding a way to create functioning blood vessels that supply the necessary nutrients to the organ. New research from the Rensselaer Polytechnic Institute in New York may have found the answer to this dilemma, with a new technique to 3D-print living skin with complete vascular networks.
While some artificial 3D-printed skin grafts are commercially available today, they do not last long and eventually fall off. This is mostly due to a lack of a vasculature system to feed the graft. “Right now, whatever is available as a clinical product is more like a fancy Band-Aid,” said Professor Pankaj Karande, member of the Center for Biotechnology and Interdisciplinary Studies (CBIS), who led the research. 
The Rensselaer Polytechnic Institute’s latest breakthrough consists of using a skin graft and combining it with more types of cells, including melanocytes and endothelial cells with pericytes, which form functional vasculature in the lab when the tissue is printed. The graft with the added cells was tested on animal wounds and was found to integrate well with the animal’s skin and tissue.
The TRL score for this Longevity.Technology domain is currently set at: ‘Early proof of concept demonstrated in the laboratory.’
The TRL score for the technology addressed in this article is: “Late proof of concept demonstrated in real life conditions.”
The new technique was tested by Yale researchers who grafted the artificial skin onto mice. The results showed that the artificial graft with the lab-made blood vessels created connections with the biological blood vessels in the mice. The integration is an important step as without blood and the flow of nutrients, a skin graft would die very quickly. Recreating biology is a very complex process, but new platforms and technology like 3D-bioprinting are making it easier and allowing researchers to build cellular structures that mimic human biology with greater precision and accuracy.
“We were pleasantly surprised to find that, once we start approaching that complexity, biology takes over and starts getting closer and closer to what exists in nature.” said Karande.
The 3D-printed living skin with blood vessels is currently in animal trials and is still in need of adjustment for humans to make it workable at a clinical level. For the process to work in humans effectively, it would require the combination of both 3D-bioprinting and gene editing technology such as CRISPR to work. Editing a patient’s donor cells would ensure that the artificial blood vessels could fully integrate and would not be rejected by the patient’s body.
“This significant development highlights the vast potential of 3D bioprinting in precision medicine, where solutions can be tailored to specific situations and eventually to individuals,” said Deepak Vashishth, the director of the Center for Biotechnology and Interdisciplinary Studies (CBIS).
So will full artificial organs and skin with lab-made blood vessels be hitting the market soon? “We are still not at that step, but we are one step closer,” Karande said. Despite it not being ready for the market just yet, this is a important milestone for the 3D-bioprinting field and brings the possibilities of new therapies and deceasing transplant lists closer than ever before.
So what’s next? More research is required to get the skin graft into humans trials and to incorporate a CRISPR element into the mix. In the field of 3D-bioprinting, this discovery opens up a wealth of opportunities and makes way for the creation of more complex artificial cellular structures that could one day match our biological organs.