Chronic, large, or non-healing wounds such as diabetic pressure ulcers are especially costly because they often require multiple treatments. It is also estimated that burn injuries account for 10 to 30 percent of combat casualties in conventional warfare for military personnel.
The major skin cells — dermal fibro-blasts and epidermal keratinocytes — are easily isolated from a small biopsy of uninjured tissue and expanded. Fibroblasts are cells that synthesize the extracellular matrix and collagen that play a critical role in wound healing while keratinocytes are the predominant cells found in the epidermis, the outermost layer of the skin.
Researchers have created a mobile skin bioprinting system that allows bi-layered skin to be printed directly into a wound. The system enables on-site management of extensive wounds by scanning and measuring them in order to deposit the cells directly where they are needed to create skin.
The cells are mixed into a hydrogel and placed into the bioprinter. Integrated imaging technology involving a device that scans the wound feeds the data into the software to tell the print heads which cells to deliver exactly where in the wound, layer by layer. The bioprinter deposits the cells directly into the wound, replicating the layered skin structure, and accelerating the formation of normal skin structure and function.
Currently, skin grafts to treat wounds and burns are the “gold standard” technique but adequate coverage of wounds is often a challenge, particularly when there is limited availability of healthy skin to harvest.
Skin grafts from donors are an option but risk immune rejection of the graft and scar formation. With the bioprinter system, new skin forms outward from the center of the wound; this only happened when the patient’s own cells were used, because the tissues were accepted and not rejected.