Imagine a world with no more donor waiting lists, no life-threatening failing organs and the option of a second chance.
According to the NHS, the average time a person spends on the waiting list for a kidney transplant is around 2½ to 3 years. While it can be shorter or longer than this, on average the waiting time is 944 days. Similarly, a shortage is found with other organs such as liver and lungs, for which more than 5,000 people are currently on the waiting list in England alone. Without a friend or family member willing to make a living donation, it can be unlikely that a person will receive a transplant. In the UK in 2017, 411 people died before the right donor was found. With our ageing population, this problem is only likely to get worse too.
What is 3D organ printing?
An artificially constructed organ is designed and produced using 3D printing techniques to be used for transplantation. In principle, printing organs would work the same as conventional 3D printing. A computer program would create a virtual representation and then it would be printed slice by slice. But instead of car or aeronautical parts – a more commonplace application – it would layer up living tissue. For example, layers of living cells may be deposited onto a gel medium or sugar matrix and slowly built up to form three-dimensional structures, including vascular systems.
What could 3D organ printing mean for us?
Firstly 3D organ printing could be used to help those who need transplants. It could also provide that vital training environment for doctors to perform critical procedures, such as heart surgery, without endangering real-life patients. 3D organ printing could also mean increasing human longevity. In the UK people are living longer than ever before, but the impact of creating artificial organs could mean that people will live longer and – crucially – healthier lives, which could potentially reduce financial strain on the health services.
What already exists?
Companies such as L’Oreal are committing resources to bioprinting in the hope of testing products on a synthetic, skin-like material. From this could come the hope of printing skin to treat severe burns, instead of skin grafts which are likely to become infected and have a lengthy recovery time. As for organs, Gatenholm suggests that replacements could be possible within our lifetimes.
Zhengchu Tan and researchers at Imperial College London have created the Cryogenic 3D Printing of Super Soft Hydrogels technique, where hydrogel solution (similar consistency to organs) is frozen and 3D printed layer-by-layer into the desired shape. It would then, in theory, be implanted onto the organ, acting as a scaffold upon which cells would be encouraged to grow.
How long away are we?
Currently, we are still far from commercially available 3D organ printers, with years of research still required. There are a number of factors which stand in the way of artificial design becoming the latest medical success story. Our organs are extremely complex. With each organ being made up of many different types of cell, there is always the risk of a foreign body reaction. Even if we are able to print 3D organs the chances of rejection are extremely high.
The high cost of research and development into printing organs is also a huge factor in delaying their adoption. However, according to the National Foundation for Transplants, “the typical kidney transplant, for instance, costs an average of $330,000 compared to the conventional 3D bioprinter which [will] cost around $10,000” if it were to be implemented, offering the opportunity for longer-term cost savings overall.
Ethically, 3D organ printing is also a concern. Many reject the idea of ‘playing God’ through the creation of human body parts. It also raises questions on the ethics of experimental testing on humans, and the lack of current international regulatory directives to guide these experiments or the standards around the printed organ themselves.
Although 3D printing technology is bringing us closer to creating organs for transplant, we are completely dependent on the speed of the R&D, as well as the individual patients in question as to the success of the procedure. With continued research, we can continue to get closer to printing organs and begin to revolutionise healthcare treatments, implants and prosthetics.