August 02, 2014
What is Bioprinting?
As a species, we’ve had incredible success building machines that have completely changed our way of life. Ranging from the first computers to today’s cellphones, we have engineered some phenomenal systems. And yet, the most precise and well-articulated systems remain those that nature has built. Our human body is an example of one such system which we are still some way away from being able to re-engineer. The quest for artificial tissues and organs remains a slow and uphill battle that can be boiled down to this: tissues and organs are incredibly complex. They possess multiple different compartments that communicate with each other, intricate microarchitecture within these compartments, and many different cell types within each compartment too. Great, now we know what we’re up against!!
Imagine a flat sheet of paper. If you pour some water over it, it seeps all the way through to the other side pretty quickly. Now think of the same sheet of paper scrunched up tightly into a ball and imagine the same amount of water being poured over it as before. It’s now much harder for the water to make it to the surfaces right at the center of the ball. That’s a very simple analogy to show the impact of surface area to volume ratio and it illustrates an important challenge when it comes to recreating solid organs – how do we build an adequate transport system to supply nutrients and remove waste since simple diffusion is no longer good enough??
Enter bioprinting. It involves recreating the 3D structure of a tissue using a fabrication technique where a computer program slices up a construct into discrete layers and rebuilds them using some sort of biomaterial extruded from a printer head that can move up, down, and side-to-side. These biomaterials are designed to mimic the architecture of the extracellular matrix in which cells are suspended. Additionally, cells themselves can be incorporated into these constructs. So you can start imagining building a complex organ step-by-step using the 3D images, such as those from MRI and CT scans, native cells from a patient, and biologically compatible materials. Obviously, this is an oversimplification of the problem at hand, but it serves to illustrate a need – that of a tool which can engage in this sort of additive rapid bioprototyping process. And that’s what Allevi has committed itself to achieving: the task of building just such a tool that is low cost to make it accessible to a large number of scientists, engineers, physicians, DIY biologists etc, but also sufficiently high-resolution to make it a powerful ally in our search for the holy grail of the artificial organ.
With over a 120,000 people in the US alone on waiting lists for organs and others experiencing chronic problems due to the long-term damaging effects of post-transplant immunosuppression, I believe we have to throw everything we can at this problem. As a community of scientists, we’ve already succeeded in bringing together multidisciplinary teams of basic scientists, physicians, and engineers to take on the biggest challenges to human health such as cancer, AIDS, and now organ regeneration. What we lack though, are ways of recreating the three-dimensional environment of cells, tissues, and organs within the body. Here at Allevi, we hope to address that problem and fundamentally change the way science is done.