Imagine you are suffering from liver disease, in desperate need of a transplant. Odds are you would be part of a long waiting list to receive a donated organ. What if you could have a brand new organ created for you, as you are being prepped for surgery? What if you were told, as a type 2 diabetic, that after years of insulin injections and blood-glucose monitoring, a specialist could grow and implant an additional, miniature pancreas to assist your own in proper insulin production? What if you could have any of these things, with no risk of tissue rejection, because these organs and tissues are created using your own stem cells?
In the next 10–15 years, researchers expect to be able to cure (rather than simply treat) organ disease, by engineering new, healthy “tissue on demand.” Numerous research groups have already made headway in the science of bioprinting, a medical application of 3D-printing technology.
Three-dimensional printing itself is not new. Originally developed in the late 1980s, it has thus far been used to produce a wide variety of items, such as prototypes of appliances or food products. The technology is based on depositing droplets of material, layer upon layer, to build up a 3D form, with help from a computer-aided design (CAD). According to Hod Lipson, director of Cornell University’s Creative Machines Lab, “Any shape you can imagine and that you can define in a computer design file, you can fabricate.”
Bioprinting may seem like a revolutionary concept, but it got its start when Thomas Boland modified a standard inkjet printer to deposit human cells back in 2003. The technology has been continuously refined and explored since.
The bioprinting process begins with the preparation of “bio-ink,” which consists of human cells and a slurry of nutrients to help the cells grow. The ink can be made from a sample of your own stem cells; this means tissue rejection due to the genetic variation of donors may soon be a thing of the past. Your personalized ink is loaded into an ink cartridge and printed on layers of hydrogel, an inert substance that serves as a placeholder for the cells. Researchers then rely on the natural behaviour of the cells, letting them fuse together and grow as they would within the human body. This growth phase may happen inside a “bioreactor,” where the new organ can be fed and provided with an ideal environment to mature.
One major roadblock keeps this technology in its infancy: the as-yet inability to re-create the complex vascular and microvascular systems needed to feed, oxygenate, and remove waste products from the assembled tissues. Despite this obstacle, though, the technology has the potential to completely change the face of medicine. According to a recent article in Time, this potential has many investors interested. Capital stock related to this research tends to rapidly grow in value. One can only imagine the excitement of investors to hear that Organovo, an industry leader, aims to create a fully functioning liver by the end of this year or that Hangzhou Dianzi University in China has grown a working kidney that researchers were able to keep alive for 30 days. Bioprinting may also come to play a large part in drug and cosmetic testing, possibly making testing on animals obsolete, as well as provide the potential for surgeons to practise on living organ systems instead of cadavers. Lipson also suggests that bioprinting will further the science of “personalized medicine,” offering doctors and nutritionists the ability to print out food, medication, and supplements with the ideal composition for each individual patient. What is now a roughly $2-billion industry is expected to be worth more than $10 billion by 2021.
Information-technology research firms, such as Gartner Inc., predict that 3D-printing technology, and bioprinting in particular, will spark heated debates over its regulation by the year 2016. Pete Basilier and his colleagues, consultants and researchers in 3D-printing technology at Gartner, released a report at the end of 2013 discussing trends they expect in the 3D printing industry. Much of the discussion centres on the medical applications of bioprinting. There is concern that it is advancing faster than the ability of regulatory agencies (such as the U.S. Food and Drug Administration) to control it.
Basilier calls the research behind bioprinting “well intentioned,” but cautions that “3D-bioprinting facilities with the ability to print human organs and tissue will advance far faster than general understanding and acceptance of the ramifications of the technology.” The Gartner report says that a full-scale societal debate is inevitable, due to the moral and ethical questions that will arise as more information about the technology and its implications is available.
Will people object to the creation of artificial body parts on religious and cultural grounds? Will the technology be applied to darker purposes, such as testing the effects of biological weapons on human tissue? Whatever issues do arise, it is certain that the education of the public, and of whichever set of authorities attain control over bioprinting regulation, will be key to the successful application of this technology.