When it comes to problems faced by the medical world today, the shortage of organ donors is pretty high up the list. Currently, more than 10,000 people in the UK need a transplant. Every day, three of these people die because a suitable organ is not identified. It is clear that the demand for organs is enormous, and if a process was to be developed that could solve this problem, many lives would be saved. Could a recently developed process, ‘Bioprinting’, be the solution to this seemingly impenetrable problem?
Bioprinting itself is a rather strange concept. Picture a typical inkjet printer, the kind of appliance you are likely to have in your own home. Now, imagine that instead of the ink cartridges only being able to move from left to right, they are able to also move back and forth, up and down. Finally, try to envisage that instead of ink, the printer is spraying body cells and biopaper, a biocompatible water-based gel. This is a simplified set up of a bioprinter, and when put into use, it is possible for this kind of printer to literally print out functioning human body tissue.
The printer works in two steps. First, a layer of biopaper is sprayed onto a printing surface, and then a ring of body cells is printed on top of that. This happens repeatedly, until a stack of body cells has been deposited, supported by a stack of biopaper. At this point, the natural phenomena of self-assembly takes over the process. Self-assembly is the name put to the incredible feat that an embryo undergoes when it slowly develops into a healthy, functioning human. It also is the reason that individual strands of DNA are able to bond perfectly to form the famous double helix structure that DNA invariably has. Self-assembly is basically a term to describe the wondrous organised form of nature. As a result, the cells that have been sprayed onto the biopaper are able to rearrange themselves into their correct positions and then fuse to form the structure of a blood vessel.
Although this concept seems to be one that could have been taken straight out of sci-fi, a Japanese scientist, Makoto Nakamura has actually succeeded in printing a tube of living cells. In 2002 Nakamura purchased a home-use Seiko Epson printer and tried to print living cells with it. As you might expect, the printer didn’t react fantastically to this new ‘ink’ and the print nozzles quickly became clogged. After a number of presumably bizarre phone calls, a member of staff at Epson agreed to provide him with technical support for this unusual endeavour. By 2003, Nakamura announced that cells had survived the printing process and he became one of the first researchers to have ever produced living structures through inkjet printer technology.
In the eight years that have passed since that breakthrough, the area has been heavily researched and some exciting potential applications have been suggested. It seems that bioprinting could induce a medical revolution.
A potential application is the bioprinting of fully-functioning organs, such as kidneys or livers. It is possible that an entire kidney could be printed in a matter of hours, and in such a way that surgeons and doctors could effectively have organs on demand. The organs would be created from a culture of the patients’ cells, so the chance of the new organ being rejected is vastly reduced. It is also possible that in the future, bioprinters could apply cells directly to the human body, allowing doctors to spray cells onto wounds and burns to heal them swiftly and without risk of infection.
From a more cosmetic point of view, bioprinters could be used to create the illusion of everlasting youth. Young adults could have their faces scanned and saved, so that in the future, the cell structure of the young face could be bioprinted onto the face of the person as they age, replacing the ageing cells and keeping the client looking youthful.
For the present, these applications are still only highly anticipated ideas, and have yet to be performed in any practical sense. However, the prospect of on-demand organs is not one that can be taken lightly. Organ transplant waiting lists would be a thing of the past, and a huge number of lives would be saved. For now, all we can do is keep a keen eye on the progress of bioprinting, and hope that, in the future, those underappreciated household printers could be the key to a medical miracle.
Image credit – Chris Campbell