Bioprinted Aorta Shows Promise for Cardiovascular Disease Treatment

Yale researchers have built a 3D-bioprinted synthetic aorta that they have successfully implanted into rats. This technology could advance the treatment of cardiovascular diseases such as coronary artery disease or peripheral arterial disease by allowing scientists to engineer and replace blood vessels in humans. The team recently published their findings in Scientific Reports.

Through this new approach, scientists could use an individual’s own cells, or cells from a donor, to rapidly create custom-designed tissues that match the size and shape of the parts of vasculature to be replaced. Current treatments for severe cardiovascular disease include the use of grafts made from a patient’s own tissues (autologous) or synthetic materials. However, autologous grafts require invasive surgery and have a significant failure rate, and synthetic grafts are limited to large blood vessels and prone to leakage and harmful bacterial colonization.

Bioprinted vasculature could offer a better solution.

“This would be another alternative for people who are suffering from cardiovascular disease that allows them to maintain a higher quality of life,” says John Geibel, DSc, MD, professor emeritus of surgery (gastrointestinal) and of cellular and molecular physiology, and the study’s principal investigator.

Previously, scientists have tried to bioengineer tissues using a bioreactor, a chamber with a porous tube at its core into which they would inject the cells. The major downside of this method is that it is time-consuming—it can take weeks to create viable tissues.

In the new study, the researchers investigated the feasibility of bioprinting aortas. They cultured the main cells that make up the aorta—aortic cells, smooth muscle cells, and fibroblasts—from rats. Then, they loaded syringes into the bioprinter, which ejected these cells onto a rolling stainless-steel tube. After letting the cells incubate for a couple of days, the bioprinted aortas were ready for implantation.

The researchers tested their synthetic vascular structures in 20 rats. Twenty additional rats underwent the same surgical procedure without the implantation of the aorta. Rats in both groups resumed normal behavior following surgery and remained in good health. Notably, the procedure was also successful in rats who received aortas built from the cells of a different animal.

This is proof-of-concept of using bioprinted vasculature to treat cardiovascular diseases, the team says. “You might think it’s a far stretch from a rat to a human, but it isn’t,” says Geibel. “It’s just a matter of sizing—humans will require a lot more cells.”

The potential to use cells from a donor could help further reduce the time a patient waits to receive a bioprinted vessel. “Theoretically, we wouldn’t need to collect the cells from the patient with a cardiovascular disease,” Geibel says. “We could collect them from another individual and begin culturing them so that we have enough cells ready to go.”

The ability to bioprint human vasculature within days could have lifechanging implications, Geibel says. People with diabetes-related foot conditions, for instance, often have poor circulation that reduces blood flow to the feet. If left untreated, an amputation can be necessary. Custom-made blood vessels could be a new treatment for the condition that can help save the foot.

“You know the old adage—'one small step for a man, one giant leap for mankind,’” Geibel says. “This is the first step to get us toward technology in the future that will allow us to change how we help patients in a way that is dramatic.”