This post is just something I thought of writing after I finished reading a paper by Anthony Atala in Nature (DOI: 10.1038/nbt.2958).
Let me jump straight into the point. Most of my professors dispose the research being done in relation with 3D printing by calling it a hype. But is it? I think not. Once you look past the technical jargons mentioned in the paper above, or in any paper for the matter of fact, once you start thinking of the impact that this technology has, once you think of the lives you can bring back, 3D printing will give you a new mindset. Most people associate 3D printing with rapid prototyping, making missing Lego blocks, tools for space maintenance, etc. Apart from all these fancy use cases, it is now (2014 with reference to the paper) possible to print tissues. Real tissues that can mimic human ones. Tissues that can be used as a replacement for would healing, for liver reconstruction, etc. This can be done with the highest possible resolution to mimic all biological constituents, even at the cellular level. This infact resulted with an interdisciplinary approach to science.
Charles W Hull first described a technique called stereolithography – which is something similar to the concept of depositing material layer by layer to form a 3D structure. This was done back in 1980s. And the same technology is being used to print custom made products. And we now call it 3D printing. Apart from the age old application for human use (printing 3D scaffolds), it is now used to make stents, splints and dental fixtures! Applications are limitless.
3D printing of tissues is not an easy process. We need some sort of spatial control over the placement of cells and other elements – especially if we follow the stereolithography technique. Exact spatial arrangement is needed to create a fully functional replica of tissues. And many different approaches are being followed currently.
- Biomimicry is one such idea. Here, we try to print the exact same thing we see in nature to get its full functionality – here, resolution of printing is critical. Replication at the micro level is really hard to achieve. The required resolution is calculated from bio imaging, engineering and biophysics. This is what guys at Stanford did with an innocuous creature called Gecko.
- Autonomous self assembly is a biologically inclined technique – It requires deep knowledge starting from the embryonic stage of organ development. This knowledge is then applied to let the tissue grow by itself, and make its own extracellular matrices – and develop into an organ that eventually can be implanted into the human body. This autonomous self assembly and patterning is achieved by using proper signaling, and environmental manipulation.
- Use of Mini-Tissues to build bigger tissues – like legos. Mini-tissues are, in general, the smallest functional components of a tissue.Eg: If you take the case of Kidney – nephrons are the basic functional component. So, such components are manipulated to come together like in self assembly – to create “macro” tissues and later, a full organ. These functional components can be 3D printed with a highest possible resolution OR they can be collected from nature by direct extraction (solves the issue of compatibility after organ development).
It doesn’t really matter to decide upon which method is the most feasible. What matters is that such amazing feat is possible with a technology that most people (still) regard as a hype.
Maybe in 10 or 15 years, scientists will be able to create a human being with real organs (from bio-engineering), real emotions (from artificial intelligence), ability to think and make decisions (from robotics), and learn ( from auto-text-prediction-tech 😛 ) – the only question then will be whether to pigment the being with dark or light skin.