Bioprinted Aortas Offer New Hope for Vascular Repair

Current treatment options for severe cardiovascular diseases include using grafts made from a patient's own tissue (autologous) or synthetic materials. However, autologous grafts require invasive surgery and are associated with a significant failure rate, while synthetic grafts are typically limited to large blood vessels and are prone to leakage and bacterial colonization. A new approach, bioprinted vasculature, may now offer a more effective solution.

Researchers at Yale School of Medicine (New Haven, CT, USA) have successfully created a 3D-bioprinted synthetic aorta, which they implanted into rats. This breakthrough technology has the potential to revolutionize the treatment of cardiovascular conditions such as coronary artery disease and peripheral arterial disease by enabling the engineering and replacement of blood vessels in humans. Through this approach, scientists could use a patient’s own cells or cells from a donor to quickly create custom-designed tissues that precisely match the size and shape of the blood vessels to be replaced. While previous attempts at bioengineering tissues relied on a bioreactor—a chamber with a porous tube into which cells were injected—this method has a significant drawback: it is time-consuming and can take weeks to generate viable tissues.

In this new study, the researchers focused on the feasibility of bioprinting aortas. They cultured the main cells that form the aorta, including aortic cells, smooth muscle cells, and fibroblasts, from rats. These cells were loaded into syringes and placed in a bioprinter, which then ejected the cells onto a rolling stainless-steel tube. After allowing the cells to incubate for a couple of days, the bioprinted aortas were ready for implantation. The researchers tested the synthetic vascular structures in 20 rats, while another group of 20 rats underwent the same surgical procedure but without the implantation of the aorta. The findings, published in Scientific Reports, showed that rats in both groups returned to normal behavior after surgery and remained healthy. Interestingly, the procedure also proved successful in rats that received aortic grafts created from cells of a different animal.

This study serves as proof-of-concept for the use of bioprinted vasculature in treating cardiovascular diseases. According to the research team, the ability to use donor cells could further reduce the waiting time for patients needing bioprinted vessels. The potential to bioprint human vasculature in just a few days could have life-changing implications. For example, people with diabetes-related foot conditions often suffer from poor circulation, which can reduce blood flow to the feet. If untreated, amputation may become necessary. Custom-made blood vessels could offer a new treatment option, potentially preventing amputation and saving the foot.

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