At MBC Biolabs, an incubator for biotech startups in San Francisco’s Dogpatch neighborhood, a team of scientists and interns working for the small startup Prellis Biologics have just taken a big step on the path toward developing viable 3D-printed organs for humans.
The company, which was founded in 2016 by research scientists Melanie Matheu and Noelle Mullin, staked its future (and a small $3 million investment) on a new technology to manufacture capillaries, the one-cell-thick blood vessels that are the pathways which oxygen and nutrients move through to nourish tissues in the body.
Without functioning capillary structures, it is impossible to make organs, according to Matheu. They’re the most vital piece of the puzzle in the quest to print viable hearts, livers, kidneys and lungs, she said.
“Microvasculature is the fundamental architectural unit that supports advanced multicellular life and it therefore represents a crucial target for bottom-up human tissue engineering and regenerative medicine,” said Jordan Miller, an assistant professor of bioengineering at Rice University and an expert in 3D-printed implantable biomaterial structures, in a statement.
This real-time video shows tiny fluorescent particles – 5 microns in diameter (the same size as a red blood cell) – moving through an array of 105 capillaries printed in parallel, inside a 700 micron diameter tube. Each capillary is 250 microns long.
Now, Prellis has published findings indicating that it can manufacture those capillaries at a size and speed that would deliver 3D-printed organs to the market within the next five years.
Prellis uses holographic printing technology that creates three-dimensional layers deposited by a light-induced chemical reaction that happens in five milliseconds.
This feature, according to the company, is critical for building tissues like kidneys or lungs. Prellis achieves this by combining a light-sensitive photo-initiator with traditional bioinks that allows the cellular material to undergo a reaction when blasted with infrared light, which catalyzes the polymerization of the bioink.
Prellis didn’t invent holographic printing technology. Several researchers are looking to apply this new approach to 3D printing across a number of industries, but the company is applying the technology to biofabrication in a way that seems promising.