In 2001, Anthony Atala became the first surgeon to build a human bladder and implant it, helping pioneer the field of bioprinting.
At the time, Atala was using a multistep process. First, he would create a frame from biodegradable, synthetic polymers, which are essentially plastics. Then he’d paint cells grown from the patient’s bladder onto the frame with a custom 3-D printer — a technique Discover detailed in a profile of Atala last year.
Now, Atala and a team from the Wake Forest Institute for Regenerative Medicine have combined both processes with a new tabletop device called an integrated tissue organ printer.
A scanner traces the patient’s body part, creating instructions for the printer’s three ink nozzles. The “ink” is a clear gel mixture of mature tissue cells, immature stem cells and polymers designed to mimic real tissues’ consistency. The ink looks syrupy at first, then hardens to resemble the texture of gelatin. It’s printed in a layered lattice, which leaves tiny channels throughout the organ that act like blood vessels and allow nutrients to be dispersed through the tissue.
Atala has now printed an ear, jawbone and muscle tissue with the integrated printer, all of which held their shape after being implanted into rodents. Blood vessels grew into the microchannels, and the rodents’ cells proliferated, making the implanted tissue more resilient over time.
Printed, personalized organs for human transplants are a long way off, but Atala’s studies show scientists are getting ever closer to finding a technological solution to one of medicine’s greatest challenges.
