Since 1954, when Dr. Joseph Murray and Dr. David Hume performed the first live kidney transplant, organ transplantation has saved the lives of hundreds of thousands of Americans in end-stage organ failure. According to a survey conducted by Donate Life America, 90% of American adults support organ donation. However, despite widespread support, there is a shortage of available organs; in 2013, 28,953 patients received an organ transplant while 94,222 patients on the UNOS waiting list did not– a ratio greater than 3:1. Each day, 18 patients die awaiting an organ.
Currently, organs are harvested from both living and deceased donors, then transplanted into a matched patient. The process requires stringent legal guidelines and speed, as organs deteriorate rapidly when the body expires. Furthermore, there is a possibility that the immune system of the recipient will reject the transplanted organ.
Scientists have tested the possibility of biologically engineering organs in the lab. A tissue donation from the organ recipient is used as a scaffold upon which stem cells stimulated to develop into the appropriate cell type can grow. The tissue can be biologically engineered to exactly match the recipient’s original tissue type, eradicating the possibility of rejection. The first bioengineered– and transplanted– tissue was created in 2011 at Karolinska University Hospital in Stockholm Sweden. The construction of the synthetic trachea took only 10 days, and the recipient experienced no adverse effects.
10 days to grow a fully-functioning organ may seem like a short amount of time, but researchers at Wake Forest University have developed a process to create kidneys in only 7 hours. The process is modelled after 3-D printing– now a commonly used technology. First, a large amount of live kidney cells are cultured in a petri dish. After blending the kidney cells with hydrogel– a nutrient-rich, water-based gel material used for creating a scaffold of the kidney structure– the mixture is inputted into a machine that “prints” the kidney based on a computer model constructed from CT scans of the recipient. The formulaic, layer-by-layer process by which the 3-D printer constructs the kidney allows for minor alterations to be made to the intermediate during printing. Furthermore, the 3-D printing allows for the development of an intricate vascular system in the organ.
3-D printed kidneys are miniature versions of their real counterparts, but they have been shown to be able to perform the basic functions of a kidney– filtering toxins, balancing solute concentration, and producing urine– with relative success. However, researchers predict years, if not decades, before the technology is clinically implemented. Currently, the complexity of the printed organs does not match that of the real tissue, and functions are rudimentary. However, as technology improves, the procedure is expected to confer significant advantages to patients awaiting organ transplantation; with minimal wait times and close to zero chance of bodily rejection, 3-D organ printing is heralded as a frontier in organ transplantation.
Check out this TED talk to see Anthony Atala, Director of the Wake Forest Institute for Regenerative Medicine, speak about (and show!) current progress in 3-D organ printing.