A team of U of T engineering students led by Dr. Axel Guenther, an associate professor in the Department of Mechanical and Industrial Engineering, has created a 3D-printing device that could potentially revolutionize modern medicine.
The PrintAlive Bioprinter, inspired by the need to engineer tissue architecture using a scalable technology, uses microfluidics technology to produce 3D skin grafts for burn patients by using the victim’s own skin cells.
Following a severe burn, it is difficult for the body to regenerate the skin layers required for survival in an adequate amount of time, thus making the patient susceptible to infections, scarring, and other complications. It is often the case that a skin culture is grown from the patient’s own skin cells, which can then be used to dress the wound. As time is a critical factor for burn victims, growing a culture of skin may not be the best option given that the process usually takes at least 14 days.
The bioprinter developed by Guenther’s team can prove to be especially useful in such cases.
The device uses the patient’s own skin cells as ink for the printing process. Small channels within the cartridges are filled with an appropriate liquid medium that nourishes the skin cells. Because skin is made up of two main layers, two separate channels are used.
“To produce a sheet of skin that maintains its natural structure with the epidermal layer on top of the dermal layer, two micro-channels are stacked one above the other, each of which independently [extrudes] a paste-like sheet,” explained Lian Leng, a PhD candidate in the Department of Mechanical and Industrial Engineering at U of T, adding “As the two sheets come out, they stick together, forming a bi-layer of soft material.”
Grafts, instead of continuous sheets, are used to minimize the number of skin cells required in the process.
Although the possibilities for the new technology are exciting, the team faced many challenges.
“Any technology that targets biological application needs to be validated in-vitro, meaning on an organism, and ultimately in-vivo, that is, to be tested on animals,” said Guenther. “This can make developing the technology a time-consuming process and may require extensive funding and resources before it can reach human clinical trials,” he added.
Thus far, the technology has been tested on mice with severe burns. “More animal experiments are needed to optimize material composition and see how we can improve healing on mice,” said Leng.
The researchers are also hoping to facilitate the mass production and commercialization of the technology for the benefit of other research facilities and, eventually, of patients.
“We hope that this technology can ultimately be transitioned into the operating room and in turn reduce the need of surgery to be performed on burn victims; we not only have the technology and infrastructure for this this project, we also have the means of translating this technology into a clinical setting,” said Leng.
It is possible that the technology may be available for human clinical trials within two to three years.
Guenther’s team has won a number of awards, including the Grand Challenges Canada grant and the 2014 Canadian James Dyson Award, for their cutting-edge research.
