In Situ Bioprinting of the Skin for Burns was presented at the American College of Surgeons Clinical Congress Researchers from the Wake Forest Institute for Regenerative Medicine (Weixin Zhao, Tamer Aboushwareb, Dennis Dice BS, Anthony Atala, James J Yoo) showed off the results of a unique experiment involving a printer that uses living cells as its “ink.” Using an inkjet printer and cartridges full of living tissue, the researchers demonstrate rapid healing in animals. Tests on mice revealed advanced healing by both the second and third week of recovery, with complete closure and formation of scar tissue by week three in treated (but not untreated) subjects. Covering burns and related wounds is of critical importance because any loss of full-thickness skin of more than 4 cm in diameter will not heal by itself. This treatment will be important for 10,000 to 40,000 people in the USA each year and about twenty times that number worldwide.
The printer has two heads, one of which ejects skin cells mixed with fibrinogen (a blood coagulant) and type I collagen (the main component of the connective tissue in scars). The other head ejects thrombin (another coagulant).
Like the components of quick-setting resins which must be kept separate until mixing causes a chemical reaction that hardens the resin, the products of the two print heads mix to immediately form fibrin, yet a third protein involved in the clotting of blood. The whole confection is topped by a layer of keratinocytes (i.e. skin cells), which are also printed.
Future iterations of the research will be conducted on pigs (which have skin that more closely resembles that of humans), and it’s not clear when, if ever, such a device might appear in a field hospital in Afghanistan, not to mention your local burn center.
* Hospitalizations for Burn Injury Per Year in the USA: 40,000 total, including 25,000 admissions to hospitals with specialized burn centers
* Total Body Surface Area Burned (TBSA): Over one-third of admissions (38%) exceeded 10% TBSA, and 10% exceeded 30% TBSA. Most included severe burns of such vital body areas as the face, hands and feet.