3-D Printed Ear Bones Grow in Mice

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I am neither an entrepreneur nor a technology visionary. (I had initially scoffed that Web pages would simply be glorified Yellow Page ads.) I am not an early adopter of technology. I am more a third-generation user, typically all-in once my skepticism has been allayed. (While I was content with my flip-phone with its rudimentary camera, I am THRILLED that I discovered the elegance and power of the smartphone. How did we ever live without an iPhone?)

Needless to say, I scoffed at the idea of 3D printing. So you can print 3D puzzles, big deal. So you can print a model tower for an architecture presentation, big whoop. Oh, me. I am so NOT a visionary!

Today’s blog is on how 3D printing is changing science and medicine, one tiny ear bone at a time.

According to Gizmag.com, 3D printed tissues and organs have shown real potential in addressing shortages of available donor tissue for people in need of transplants, but the biggest obstacle to success has been having them take root and survive after implantation.

But in an epic life-changing success, researchers at Wake Forest Baptist Medical Center have used with a newly-developed 3D printer to produce human-scale muscle structures that matured into functional tissue after being implanted into animals.

Researchers have been exploring bioprinting as a means of replacing damaged tissue for several years now. The difficulty in replicating the complexities of human tissue has been extremely difficult, however, with scientists testing the waters with specialized bio-inks and various purpose-built printers in an effort to produce usable, engineered tissue. Every failure is a success, though, in the search for the perfect “ink” for such enterprises.

After more than a decade, researchers at Wake Forest Baptist Medical Center are engineering structures of adequate size and strength to implant in the human body, using the team’s Integrated Tissue and Organ Printing System (ITOP), which is claimed to overcome the limitations of previous bioprinting approaches.

It spouts water-based gels that contain the cells, along with biodegradable polymers arranged in a latticed pattern and a temporary outer structure.

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The water-based gels were optimized to promote cell growth and health. This, combined with micro-channels that allow nutrients and oxygen from the body to permeate the structure, allows the system to remain alive while it develops a system of blood vessels.

To demonstrate its capabilities when it comes to soft tissue structures, the team used the system to produce muscle tissue, implanting it in rats and finding that two weeks later it was robust enough to permit blood flow and induce nerve formation. Using human stem cells, the system also printed jaw bone fragment large enough for a facial reconstruction and implanted them in rats. Five months later, the structures had matured into vascularized bone tissue.

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Previously, engineered tissue structures without ready-made blood cells needed to be smaller than 200 microns in order for the cells to survive, but this new approach solves that problem. The researchers used ITOP to produce baby-sized ear structures measuring 1.5 in (3.8 cm) long, which were implanted under the skin of mice in the lab and went on to show signs of vascularization one and two months later.

Further adding to ITOP’s potential is its ability to take data from CT or MRI scans and make individually designed (bespoke) tissue for patients. So if a patients is missing a particular piece of tissue, such as a section of ear or nose, for example, the system could theoretically reproduce a precise replica.

“This novel tissue and organ printer is an important advance in our quest to make replacement tissue for patients,” says Anthony Atala, senior author on the study. “It can fabricate stable, human-scale tissue of any shape. With further development, this technology could potentially be used to print living tissue and organ structures for surgical implantation.”

The researchers will continue to explore the approach to track longer term results. Their current study is published in the journal Nature Biotechnology.

Technology limited only by imagination. H.G. Wells and Mary Shelley, what do you think? Any ideas? And Edward Scissorhands, ready for a makeover?

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