Researchers often test experimental pharmaceutical therapies using laboratory-grown human tissues. Unfortunately, creating these materials can be complex and expensive, leading many researchers to turn to alternative approaches such as 3D bioprinting – itself a slow, laborious process. Now, however, a new printing system shows promise to dramatically reduce the time it takes to create lab-quality tissue samples. And instead of layering delicate cellular material, the device relies on acoustic waves to assemble a wide range of biological components.
A biomedical engineering team from the University of Melbourne’s Collins BioMicrosystems Laboratory recently designed a new machine capable of what they call ‘dynamic interface printing’. As described in a study published in the journal Naturethe 3D bioprinter can already produce samples ranging from soft brain matter to denser bone and cartilage, while overcoming many current industry hurdles.
“Just as a car requires its mechanical components to be precisely arranged for proper operation, so too do the cells in our tissues need to be properly organized,” said David Collins, head of the Collins BioMicrosystems Laboratory, in a university profile. “Current 3D bioprinters rely on cells aligning naturally without guidance, which poses significant limitations. These issues often include accidentally damaging the cells during printing, as well as limitations on the complexity of the tissue structure.”
“Improper cell positioning is a major reason why most 3D bioprinters fail to produce structures that accurately represent human tissue,” said Collins.
[Related: Scientists have 3D bioprinted functioning human brain tissue.]
Standard bioprinting also currently requires a two-step process. First, equipment slowly builds a structure of living cells layer by layer, often over the course of several hours. That amount of time often threatens the viability of cells due to their exposure in the laboratory. Once completed, researchers must physically transfer the tissues from the printer to laboratory plates for imaging and analysis. This final stage often results in damage to cell cultures rendering them useless.
However, his team’s 3D printer offers an alternative that is both safer, more customizable and much faster. Unlike most 3D printing strategies, the new device uses sound waves to vibrate microscopic bubbles in desired directions to arrange specific cells. Once in place, researchers can manipulate these basic structures to grow into more complex human tissues.
The speed at which the bioprinter completes these tasks is also exponentially faster than layer-based 3D printers. With a speed approximately 350 times faster than traditional options, the new method takes just a few seconds to complete a job. Another advantage is the ability to print directly onto a laboratory plate, leaving tissue growth undisturbed, sterile and less susceptible to damage.
The Researchers at the University of Melbourne believe so that with additional testing and improvements, medical facilities could one day have 3D bioprinters that can use a patient’s harvested cells to produce hundreds of miniature models of their specific disease in just a few minutes.