Regenerative medicine firm Humacyte has started clinical trials tissue on its bioengineered blood vessels, this week implanting the first U.S. patient with a blood vessel grown using the company’s experimental technology.

Research Triangle Park-based Humacyte has developed a way to grow blood vessels from human cells in a laboratory setting. The goal is to develop blood vessels that can be stored at hospitals and pulled “off the shelf” as needed for implantation in patients who need diseased or damaged blood vessels to be replaced or bypassed.

The first U.S. patient to receive a blood vessel developed from Humacyte’s technology was implanted with the vein in a surgery conducted Wednesday at Duke University Hospital.

“This is a pioneering event in medicine,” Dr. Jeffrey Lawson, a vascular surgeon and vascular biologist at Duke Medicine who helped to develop the technology and performed the implantation said in a statement. “It’s exciting to see something you’ve worked on for so long become a reality.”

Privately-held Humacyte had raised $22 million in a financing effort expected to reach $27 million, according to securities filings from April 2012, the most recent for the company. The company received Food and Drug Administration clearance in April to start trials involving 20 kidney dialysis patients in the United States.

The U.S. trial will focus on implanting vessels in the arms of kidney hemodialysis patients. These patients are currently treated with synthetic vascular grafts, which are prone to clotting. Doctors can also harvest a vein from the patient’s own body but the additional procedure carries risks of infection and other complications. Humacyte’s technology, which is based on research originally started at Duke University, could avoid those risks and complications.

Humacyte was co-founded by Dr. Laura Niklason, a former Duke faculty member who is now at Yale University. Niklason and Lawson have collaborated over the last 15 years on research for engineering blood vessels. Humacyte develops its blood vessels from human cells, smooth muscle cells that are seeded on a biodegradable scaffold formed in the shape of a blood vessel. The smooth muscle cells grow on the scaffold and eventually form a vein. But human cells are later washed away leaving a collagen structure.

Removing the human cells eliminates the risk of rejection and also results in a shelf-stable product that can be stored and used as needed. When implanted, living tissue grows into the Humacyte implant, which carries more of the cellular properties of a native blood vessel compared to synthetic implants. Humacyte’s bioengineered blood vessels were tested in 2010 and 2011 in baboons, setting the stage for the human trials that have begun.

If Humacyte’s trials in hemodialysis patients are successful, the company could move on to developing grafts for heart bypass surgeries and blocked blood vessels in the limbs.

“We hope this sets the groundwork for how these things can be grown, how they can incorporate into the host, and how they can avoid being rejected immunologically,” Lawson said. “A blood vessel is really an organ – it’s complex tissue. We start with this, and one day we may be able to engineer a liver or a kidney or an eye.”