University of Toronto researchers have outdone themselves this time with the creation of a handheld 3D skin printer that deposits even layers of skin tissue to cover and heal deep wounds. The device deposits and sets within two minutes, making what the researchers believe is the first device that forms tissue in situ.
The research is led by PhD student Navid Hakimi under the supervision of associate professor Axel Guenther of the faculty of Applied Science & Engineering and in collaboration with Dr. Marc Jeschke, director of the Ross Tilley Burn Centre at Sunnybrook Hospital and professor of immunology at the University of Toronto.
Skin is constructed of three layers – the epidermis, dermis, and hypodermis – that could all be damaged in patients with deep wounds. The current ideal treatment for deep skin wounds is called split-thickness skin grafting. This method of treatment takes healthy donor skin and grafts it onto the surface epidermis and part of the underlying dermis. However, with large deep wounds, a significant amount of healthy donor skin is required to graft all three layers and is typically not available. This leaves a partially covered wound or an improperly covered wound that leads to poorer healing outcomes.
This ‘skin dispenser’ could offer a solution to these barriers, and works a lot like a white-out tape roller, but on a much larger scale with a microdevice that forms tissue sheets instead of a tape roll. Vertical stripes of “bio-ink” made up of protein-based biomaterials including collagen run along the inside of each tissue sheet. Collagen is the most abundant protein in the dermis, and fibrin, a protein involved in wound healing.
“Most current 3D bioprinters are bulky, work at low speeds, are expensive and are incompatible with clinical application,” explains Guenther.
“Our skin printer promises to tailor tissues to specific patients and wound characteristics,” adds Hakimi. “And it’s very portable.”
The handheld device is the size of a small shoebox and weighs less than a kilogram. It also requires minimal operator training and eliminates the washing and incubation stages required by many conventional bioprinters.
Although many tissue-engineered skin substitutes exist, they are not yet widely used in clinical settings. This entices the researchers to add several capabilities to the printer, including expansion of the coverable wound size. With the team combining forces with Sunnybrook Hospital, they have more plans to perform in vivo studies with clinical trials on humans. This brilliant technology has the opportunity to literally shape skin and revolutionize the face of burn care.