Researchers at Columbia University’s Irving Medical Center have developed a method to create three-dimensional bioengineered skin grafts. To date, bioengineered skin is typically created in flat sheets. However, these are difficult to fit to complex anatomy, such as the hand, and so these researchers have designed a more sophisticated technique that combines laser scanning, 3D printing, and cell culture to create seamless three dimensional skin grafts. For instance, the researchers have already created a skin “glove” that could be useful in replacing skin on the hands by simply slipping it over the hand (just like a glove).
Replacing skin that has been damaged is a challenge. Traditional skin grafts require skin to be harvested elsewhere before application to the damaged area, which obviously isn’t ideal. Researchers have been developing bioengineered skin by combining human cells with biomaterials, but so far these constructs tended to be simple sheets which are not easy to cut and firmly affix to our undulating anatomy.
To address this, the Columbia researchers have developed a technique that can create three dimensional constructs that more closely resemble clothing that can simply be pulled on over damaged tissue. Aside from ease of application, the method requires the constructs to be designed for each situation, enabling personalized constructs that are perfectly tailored for each patient.
“Three-dimensional skin constructs that can be transplanted as ‘biological clothing’ would have many advantages,” said Hasan Erbil Abaci, a researcher involved in the study. “They would dramatically minimize the need for suturing, reduce the length of surgeries, and improve aesthetic outcomes.”
The approach involves laser scanning the area of the body onto which the graft will be applied – for instance, a burn injury that has damaged most of the skin on the hand. In this case, the patient’s hand would be scanned and then the researchers can use computer-aided design to create a template for a hollow glove-like construct. The next step involves 3D printing a biomaterial substrate in the required shape and then seeding it with connective tissue proteins, such as collagen, and skin fibroblasts that can secrete connective tissue components. The researchers then seed keratinocytes on the outside of the graft to form an epidermis layer.
After a culture period, the graft can be slipped onto the injured hand just like a glove. “We hypothesized that a 3D fully enclosed shape would more closely mimic our natural skin and be stronger mechanically, and that’s what we found,” said Abaci. “Simply remaining faithful to the continuous geometry of human skin significantly improves the composition, structure, and strength of the graft.”
Study in journal Science Advances: Engineering edgeless human skin with enhanced biomechanical properties