Bioengineered skin grafts that fit like a glove — ScienceDaily

Bioengineers at Columbia University seem to have solved this problem by devising a way to grow artificial skin into complex three-dimensional shapes. For example, it is now possible to construct a seamless “glove” of skin cells that can be easily slipped onto the skin. A badly burned hand.

Researchers reported their findings in a paper published Jan. 27 scientific progress.

“A three-dimensional skin structure that can be implanted as a ‘biological garment’ has many advantages,” said lead developer Hasan Erbil Abaci, Ph.D., assistant professor of dermatology at Columbia University’s Vagelos College of Physicians and Surgeons. said. “It dramatically minimizes the need for suturing, reduces operative time, and improves aesthetic results.”

The current study also revealed that continuous 3D grafts have better mechanical and functional properties than conventional fragmented grafts.

3D scaffolding

The process of creating new skin grafts begins with a 3D laser scan of a target structure, such as a human hand. Then, using computer-aided design and his 3D printing, create a hollow, transparent model of the hand. Next, the outside of the model is seeded with dermal fibroblasts and collagen (a structural protein) that generate the connective tissue of the skin. Finally, the outside of the mold is coated with a mixture of keratinocytes (the cells that make up most of the outer skin layer or epidermis) and the inside is perfused with growth medium to support and nourish the growing graft. .

With the exception of the 3D scaffold, the researchers employed the same procedure used to make the flat engineered skin, and the entire process took the same amount of time, about three weeks.

In the first test of 3D-designed skin, constructs composed of human skin cells were successfully implanted into mouse hind limbs. “It was like putting shorts on a mouse,” says Abachi. “The entire surgery took about 10 minutes.” After four weeks, the grafts were fully integrated with the mice’s surrounding skin, and the mice regained full function in their limbs.

Because mouse skin heals differently than human skin, the researchers next wanted to test the grafts on larger animals, whose skin biology more closely matches human skin biology. are planning Human clinical trials are likely to be years away.

Redesigning artificial skin

3D grafts are the first major redesign of engineered skin grafts since they were first introduced in the early 1980s. “Artificial skin started with just his two cell types, but human skin has about 50 cell types. Most research has focused on mimicking the cellular components of human skin.” ‘, he says Abaci. “As a bioengineer, I am always annoyed that the shape of the skin is overlooked and the graft is made with an open border, or rim. From the bioengineering of other organs, shape influences function. We know it’s an important factor.”

Abaci and his team realized that the availability of 3D printers would allow them to create more realistic grafts, allowing them to create the three-dimensional scaffolding needed to create artificial skin.

“We hypothesized that a fully enclosed 3D shape mimics our natural skin more closely and is mechanically stronger. That’s our finding,” says Abaci. . “Just staying true to the continuous shape of human skin greatly improves the composition, structure and strength of the graft.”

In the future, Abaci believes grafts could be custom made from the patient’s own cells. With a skin sample as small as 4×4 mm, enough cells can be cultured and grown to create enough skin to cover a human hand.

“Another attractive application is facial grafts, where wearable skin is integrated with underlying tissues such as cartilage, muscle, and bone to provide patients with a personalized alternative to cadaveric grafts. ,” says Abaci.

This study was funded by grants from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (5K01AR072131) and the epiCURE Center at Columbia University Irving Medical Center (5P30AR069632).

Dr. Abaci has a patent pending on this technology.