3D Skin Printing

3-D printing is all the rage these days, and represents the potential for near-future revolution (or current depending on your sector) in innovation. University of Madrid (UC3M)'s Centre for Technological Research has created a prototype for a 3D Bioprinter that can create functional human skin. We look at what this means, and where this could go.

How does 3D Printing actually work?

We've watched inspiring TED Talks and the potential of 3D printing, but often left out of these high level talks is the basics of what 3D printing is. 3D printing is like your regular printer at the office in many ways. Replace the inkjet with a different material, usually, liquid plastic, and you're already most of the way there. To get height, the third dimension, in most printers, the plastic works in layers from the bottom and moves up when the bottom layer is finished.

Model: 3D models are generated using computer software.

Print: The model checks for various errors, and is then redesigned, separated into layers, starting at the bottom. Printing can take days to weeks.

Other: Sometimes there are additional processes involved to finish the product, like shaving or trimming an oversized model.

They say a picture is worth a thousand words; a video surely must be a million words. Here is a sped up video demonstrating how a deer model is 3D printed.

Bioprinters

Bioprinting is taking the same principles of 3D printing, but using different materials. Instead of liquid plastic for manufacturing, the idea is to use tissues where the cell's function, properties, and viability are intact. At this stage, we can say that these printers are experimental, but their capability and potential is clear as is shown in this TED Talk. It isn't difficult to imagine the far reaching potential for this type of technology. To name just a few examples that immediately come to mind:

Animal testing: The ethics of animal testing has been questioned for several decades now, especially in the cosmetics industry. Being able to bioprint human skin cells has the potential not only to minimize animal testing1, but to produce much greater accuracy and effective testing. As this ability to produce human skin becomes more viable and cost-effective, we are likely to see its benefits in the very near future.

Organ transplant: It shouldn't surprise anyone that there is a massive shortage in organs. According to Mayo Clinic, over 120,000 Americans are waiting for an organ transplant, and 21 patients a day die due to lack of donor organs. While printing "solid organs" like the lungs is not yet possible, this is the logical next step for bioprinting technology, and this will have enormous consequences for medicine.

Human Skin Printed

The University of Madrid (UC3M)'s Centre for Technological Research with the help of the BioDan group, has created a prototype for a 3D Bioprinter that can create functional human skin. Its potential uses include, transplantation to patients, as well as testing chemical, cosmetics, or pharmaceuticals. Bioinks, the material equivalent of liquid plastic (in traditional additive manufacturing) is the critical challenge in medical bioprinting. As it is a living cell, care must be taken to ensure that the cells survive and function in a way that is as similar as possible to its natural environment.

For skin printing, it can be specific, meaning that the patient's own tissue is used (for surgeries, transplants for burn victims for example), or general, meaning that it is used from a stock of cells, for much larger industrial purposes, like general testing of various cosmetics, chemicals or pharmaceuticals2. These potentials are already close to being realized; to a small extent it's already done, but there are still many hurdles that still need to be overcome. Some identifiable challenges include:

  • Regulatory challenges--this is bleeding edge technology, and regulatory agencies need to consider various aspects of the technology, and its implications, which is often not obvious at an early stage.
  • Scaling and costs--similar to traditional printing technology, there is a point at which costs go down as the technology and productivity scales. At this prototyping stage, however, companies or other entities will often need to take a risk for future reward, which isn't always smooth.
  • Technology and science--It's often accepted as a kind of truism that the speed at which technology accelerates is often closer to exponential growth than it is to linear growth. Unlike something like processing speed, however, how fast these exciting technologies bear practical fruit are often more complicated.

1Animal testing is drawing conclusions from the similarity of the way human cells behave with that of the tested animal. There are obvious limits to what one can extrapolate from different organisms.
2https://www.sciencedaily.com/releases/2017/01/170123090630.htm