Scientists integrate blood vessels into 3D printed active skin

According to foreign media reports, when it comes to skin transplant surgery, it would be a great thing if you don’t have to obtain it from the patient’s own body, but can 3D print permanent skin grafts as needed. Now people are getting closer to this goal, because scientists have now bioprinted complete vascular active skin.

First, there are already commercially available 3D bioprinted skin grafts made from living cells. However, these are generally only intended to be used as temporary wound covers because they lack the vasculature that allows blood to flow from and into the patient’s body. As a result, the graft will eventually fail to function and fall off the patient’s own skin. To overcome this limitation, a team from Rensselaer University of Technology initially produced so-called “biological inks” by mixing two types of living cells. Although they still lack the vascular system, they are printed as skin-like structures. Recently, they collaborated with Yale University researchers to add certain “key elements” to these bio-inks. These elements include human endothelial cells that line the inside of blood vessels and pericytes that wrap around endothelial cells.

These are combined with components commonly found in bioprinted skin grafts, such as animal collagen and other structural cells. Within a few weeks, the blood vessels in the skin printed by the researchers with the new bio-ink began to grow. When these pieces of skin were transplanted onto the wounds of mice, the blood vessels of the animals began to communicate with the blood vessels in the bioprinted skin, causing the graft to be filled with blood after four weeks. “This is very important because we know that blood and nutrients are actually transferred to the graft, which keeps the graft alive,” said Pankaj Karande, research leader and associate professor. Next, researchers need to develop a way to “edit” the donor cells so that the graft is not rejected by the recipient’s body. Scientists recently described this research in a paper published in the journal Tissue Engineering Part A.