New research suggests a lab-grown vessel, once implanted, is accepted by the body as its own — even healing after damage, as occurs during repeated puncturing from dialysis needles. (Credit: Shawn Rocco/Duke Medicine)
A healthy heart needs healthy vessels to pump oxygen to the rest of the body. Cardiovascular diseases can damage these vessels, and current treatments — like grafting vessels from elsewhere in a person’s body or from synthetic sources — come with serious risks. But in March, a team of researchers announced in Science Translational Medicine that they had made blood vessels in the lab that, once transplanted into people, can turn into functionally living tissue.
Researchers at Duke University, Yale University and biotech company Humacyte collected cells from cadavers — specifically, cells from muscles that make up blood vessels and that form vessels’ inner lining. They seeded these cells onto a biodegradable mesh scaffold, where the cells created proteins to surround the structure. Then, once the structure was built, the scientists removed the cadaver cells, leaving behind the new human acellular vessel (HAV), which mimics a real artery or vein.
“The removal of the cells is important so that the vessels can be manufactured in large batches and stored on the shelf in operating rooms for implantation into any patient,” explains Heather Prichard, chief operating officer at Humacyte, who led the research.
(Credit: Jay Smith, after Sofia Echelmeyer/Uniformed Services University)
The trials were conducted in end-stage kidney patients. The researchers found that HAVs removed from patients during routine operations revealed the patients’ own cells had set up shop on the faux vessel. And, they found implanted HAVs that had been damaged by dialysis needles were repaired by the patient’s cells, suggesting the engineered vessels are capable of self-healing.
If HAVs continue to perform well in clinical trials, they could make blood vessel repair safer and more effective in the future.