Can Bioprinted Skin Substitutes Replace Traditional Grafts for Treating Burn Injuries and Other Serious Skin Wounds?

Posted on October 17th, 2023 by Lawrence Tabak, D.D.S., Ph.D.

Each year in the U.S., more than 500,000 people receive treatment for burn injuries and other serious skin wounds.¹ To close the most severe wounds with less scarring, doctors often must surgically remove skin from one part of a person’s body and use it to patch the injured site. However, this is an intensive process, and some burn patients with extensive skin loss do not have sufficient skin available for grafting. Scientists have been exploring ways to repair these serious skin wounds without skin graft surgery.

An NIH-funded team recently showed that bioprinted skin substitutes may serve as a promising alternative to traditional skin grafts in preclinical studies reported in Science Translational Medicine.² The approach involves a portable skin bioprinter system that deposits multiple layers of skin directly into a wound. The recent findings add to evidence that bioprinting technology can successfully regenerate human-like skin to allow healing. While this approach has yet to be tested in people, it confirms that such technologies already can produce skin constructs with the complex structures and multiple cell types present in healthy human skin.

This latest work comes from a team led by Adam Jorgensen and Anthony Atala at Wake Forest School of Medicine’s Wake Forest Institute for Regenerative Medicine, Winston-Salem, NC. Members of the Atala lab and their colleagues had earlier shown it was possible to isolate two major skin cell types found in the skin’s outer (epidermis) and middle (dermis) layers from a small biopsy of healthy skin, expand the number of cells in the lab and then deliver the cells directly into an injury using a specially designed bioprinter.³ Using integrated imaging technology to scan a wound, computer software “prints” cells right into an injury, mimicking two of our skin’s three natural layers.

In the new study, Atala’s team has gone even further to construct skin substitutes that mimic the structure of human skin and that include six primary human skin cell types. They then used their bioprinter to produce skin constructs with all three layers found in healthy human skin: epidermis, dermis, and hypodermis.

To put their skin substitutes to the test, they first transplanted them into mice. Their studies showed that the bioprinted skin encouraged the rapid growth of new blood vessels and had other features of normal-looking, healthy skin. The researchers were able to confirm that their bioprinted skin implants successfully integrated into the animals’ regenerated skin to speed healing.

Studies in a pig model of wound healing added to evidence that such bioprinted implants can successfully repair full-thickness wounds, meaning those that extend through all three layers of skin. The bioprinted skin patches allowed for improved wound healing with less scarring. They also found that the bioprinted grafts encouraged activity in the skin from genes known to play important roles in wound healing.

It’s not yet clear if this approach will work as well in the clinic as it does in the lab. To make it feasible, the researchers note there’s a need for improved approaches to isolating and expanding the needed skin cell types. Nevertheless, these advances come as encouraging evidence that bioprinted skin substitutes could one day offer a promising alternative to traditional skin grafts with the capacity to help even more people with severe burns or other wounds.

References:

[1] Burn Incidence Fact Sheet. American Burn Association

[2] AM Jorgensen, et al. Multicellular bioprinted skin facilitates human-like skin architecture in vivo. Science Translational Medicine DOI: 10.1126/scitranslmed.adf7547 (2023).

[3] M Albanna, et al. In Situ Bioprinting of Autologous Skin Cells Accelerates Wound Healing of Extensive Excisional Full-Thickness Wounds. Scientific Reports DOI: 10.1038/s41598-018-38366-w (2019).

NIH Support: National Institute of Arthritis and Musculoskeletal and Skin Diseases