I am sure most of you have heard of 3D printing but do you know there are companies that are making great strides in the field of three dimensional (3D) bioprinting? This may sound as science fiction but it is not. Bioprinting makes use of 3D printing and 3D-like printing techniques to combine cells, growth factors, and biomaterials to reproduce biologic parts (for lack of a better name) that imitate natural tissues. The process involves the layer by layer method to deposit materials known as bioinks* to create tissue-like structures. I am not sure about you, but this gives this accident-prone-person some solace in the fact that I may be able to replace in the future the body parts that I have been known to cut or knock off.
*Welcome to a short digression to explain bioinks; your normal blog will be resumed shortly…Bioinks are materials that imitate an extracellular environment to support living cells. They are different from other biomaterials by their ability to be placed as filaments during the additive process. These materials are formed from existing hydrogel materials from natural polymers such as gelatins, fibrin, alginates, etc. There is so much more to discuss on this particular topic but we have gotten away from the main point of today’s blog.
The recent populari
ty of 3D printing and the explosion of technology surrounding it guarantee continuing research and developments in the area of regenerative medicine. Currently, bioprinting is still experimental and is used to print tissues and organs to help in the development of pharmaceuticals but innovations are being made to incorporate the production of scaffolds used to regenerate joints, bones, and ligaments.
The process of bioprinting is a three step one, generally speaking. The first part of this process is the creation of a model that the printer would work from. This involves using computed tomography (CT) and magnetic resonance imaging (MRI) to establish the template on which the organ or bone is based and grown. If a specific organ was to be reproduced, a biopsy would be performed on it and the specific cells could be isolated and multiplied and then mixed with oxygen and other nutrients to keep them alive.
In the second step this mixture of cells, nutrients, and bioink are placed in the printer cartridge and deposited utilizing the scans taken to make an exact replica. This printer deposits this mixture in multiple layers only as thick as a human hair onto a scaffold of biocompatible material until the whole process is finished. With this process still in its infancy, the ‘infrastructure’ of an organ is lacking in the crucial elements such as working blood vessels. This means that there would be no way to get nutrients into the organ and/or remove wastes from these organs, as of yet but the research still continues.
The last part of this printing of parts involves creating a stable environment for the biological material without which the cells would die. To maintain the object produced, both mechanical and chemical stimulations are needed to send signals to the cells to control the remodeling and growth of tissues. Bioreactors help to in the following ways: they provide convective nutrient transport; they create microgravity environments; they can change the pressure causing solutions to flow through the cells; or add compression for dynamic or static loading. The different types of bioreactors assist the different types of tissues. As an example, compression bioreactors are ideal for cartilage tissue.
Researchers in this field have taken a few varying approaches such biomimicry, autonomous self-assembly, and mini-tissue. Biomimicry is just what it sounds like. It is the replication of the shape, framework, and microenvironment of a specific organ or tissue. For this process to be successful, it must be accomplished at a micro size. Autonomous self-assembly is an organization of cells from an initial state to a final pattern without external intervention. It relies upon the knowledge of cellular self-assembly and the ability to employ them. It is kind of like that old science fiction theme of robots making robots, ish. Mini-tissues are a combination of the first two processes. This approach builds organs and tissues from very small functional component pieces and assembles them together.
There is a very long way to go before biotechnology companies are actually manufacturing body parts for consumers but a lot of advancement has been made and this fascinating field has so many far reaching possibilities. Think how wonderful it would be to print a replica of your failing heart using your own cells making cellular rejection a thing of the past or how injuries or imperfections could be repaired with little invasion to the body. It is fascinating to think of the progress we could see in the next few years in the field of bioprinting.
–Janice Willson
An interesting video explaining bioprinting and the future of:
https://www.bing.com/videos/search?q=bioprinting+videos&view=detail&mid=5F9150BF05CE593EA5EF5F9150BF05CE593EA5EF&FORM=VIRE
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3635954/
https://en.wikipedia.org/wiki/3D_bioprinting
https://www.sciencedirect.com/science/article/pii/S2468217916300144
Article Photo Source: Андрей Ильин (#d bioprinter by Russian company #D Bioprinting Solutions, capable of printing live organs)
