Wednesday, February 12, 2014

3D printing the human body

Bioprinting, or the process of creating human tissues through 3D printers, is a highly contested area of technological innovation. Theoretically it could save the economy billions on a global scale, whilst boosting weak or war-torn countries' access to more affordable health care and provision, whether producing prosthetic limbs or highly customised fully-working human organs.
From a technological perspective, the rise and development of 3D printing and its capabilities will play an undeniable part in our future lives. But how does the process work?
UK-based company PrinterInks has teamed up with US startup Organovo, a company specialised in designing and printing functional human tissue for medical research and therapeutic applications, to create a visual guide to the subject.
3D printed human tissue is created by using modified printer cartridges and extracted cells, sourced from patient biopsies with respect to examining cancer cells, or stem cells. They're grown using standard techniques and cultured in a growth medium in dishes, allowing them to multiply.
Once enough cells have grown, they're collected and formed into spheroids or other shapes and loaded into a cartridge to create BioInk.
The BioInk is loaded into a NovoGen MMX bioprinter along with a cartridge of Hydrogel, a kind of synthetic matrix effectively used as a kind of scaffolding for building 3D layers of cells. The printer prints a layer of the water-based gel, followed by a layer of BioInk cells, and so on. The layered calls naturally fuse together as the layers and built upon.
The printer with its BioInk and Hydrogel cartridges
Once the desired amount of layers is printed, the printed tissue is left to mature and grow as a structure, during which time the hydrogel is removed. Other researchers experimenting with bioprinting have used a sugar and water solution as a form of support for the vascular structures to great success.

Currently printed tissues are generally used for medical research; introducing disease to monitor how the tissue reacts and how future treatments may be developed. In the future, it's very likely 3D printers will be used to create simple tissues for implanting into current organs and partial organs. The printing of whole organs, if approved, could be a reality within the next decade.
Organovo recently bioprinted its first 3D liver tissue for testing purposes, and can create 24 strips of liver tissues within a single plate. In 2010 the company also printed the first human blood vessel without the use of scaffolds.

They estimate it would currently take 10 days to print an average sized liver and lobe, but estimate the speed and efficiency with which they could create such tissue structures will greatly advance in the future. After all, it would currently take 1,690,912,929,600 hours to print a liver for every member of the human race using the process in its current form.
In the mean time, Organovo plans to market and launch its 3D liver tissue to pharmaceutical companies and research labs by the end of December, and is currently developing bioprinted breast cancer tissues alongside lung and muscle tissues. With the technology advancing at such a rate, entire organs and bodies produced by 3D printers is becoming a concrete reality, rather than a freaky sci-fi concept.
The bionic ear in all its glory
In August last year the Hangzhou Dianzi University in China announced it had created biomaterial 3D printer Regenovo, which printed a small working kidney that lasted four months. Earlier in 2013, a two-year-old child in the US received a windpipe built with her own stem cells, and Princeton University printed a 'bionic ear' using a modified ink-jet printer onto a petri dish.

Ethically and morally, concerns have been raised over ensuring the quality of the organs, and who controls the right to produce them. Others claim 3D printing human components further blurs the line between man and machine, giving us the right to 'play God' on an unprecedented scale. But there is no denying that bioprinting has the potential to revolutionise medicine and healthcare beyond what seemed possible even 20 years ago.