artificial blood vessels
© IMBA
An illustration of vascular organoids, lab-made human blood vessels, based on original data.
The researchers also demonstrated that it is possible to grow functioning human blood vessels in another species.

A team of researchers has managed to grow "perfect" human blood vessels in a Petri dish and a non-human animal for the first time.

As detailed in a study published Tuesday in Nature, organoids - biomasses grown from stem cells that mimic human organs - were grown after researchers identified an important pathway that prevents changes to blood vessels, a major cause of death in diseases such as diabetes and Alzheimer's.

"Being able to build human blood vessels as organoids from stem cells is a game changer," Josef Penninger, director of the Life Sciences Institute at the University of British Columbia and lead author of the study, said in a statement. "Every single organ in our body is linked with the circulatory system [so] this could potentially allow researchers to unravel the causes and treatments for a variety of vascular diseases."

After growing the blood vessels in a Petri dish, Penninger and his colleagues also transplanted the vascular organoids into live mice. As they discovered, the organoids developed into fully functional blood vessels, which demonstrated for the first time that vascular organoids could be grown in another species.

Blood vessels in people with diabetes will often thicken in such a way that it prevents the effective delivery of oxygen and nutrients through the body, and, over time, can lead to serious problems such as kidney failure, strokes, and heart attacks.

To test the effectiveness of the organoids as a stand-in for diseased blood vessels, the researchers put the organoids in an environment meant to simulate what it would be like to have diabetes. The blood vessels in the Petri dish responded just like they would in a diabetic human.

"Our organoids resemble human capillaries to a great extent, even on a molecular level," Reiner Wimmer, a postdoctoral researcher at the Institute for Molecular Biotechnology, said in a statement. "We can now use them to study blood vessel diseases directly on human tissue."
Daniel Oberhaus is a staff writer at Motherboard reporting on quantum physics, artificial intelligence, space, energy, and the psychedelic renaissance. daniel.oberhaus@vice.com