January 17, 2019 - 14:19 AMT
Researchers grow viable human blood vessels

Researchers have developed a way to grow stable, viable human blood vessels from stem cells in the lab, Forbes says.

The study, published in the journal Nature, significantly advances research into vascular diseases like diabetes. Indeed, the researchers used the new method to identify a human protein that contributes to diabetes-associated vascular damage, and showed that blocking its function could potentially prevent such damage.

Diabetes affects more than 420 million people around the world and its most serious complications arise from the vascular damage it causes. Specifically, diabetes patients are prone to a range of blood vessel changes, including abnormal thickening of blood vessel walls, loss of vascular cells, and disrupted cellular communication in blood vessels. Over time, this impairs circulation and can ultimately cut off the supply of nutrients and oxygen to cells and tissues in the body. This, in turn, can lead to myriad problems including blindness, kidney failure, strokes, heart damage and the need for amputations.

Exactly how blood vessel dysfunction arises and causes damage in diabetes has remained unclear, which has made it difficult to develop targeted treatments.

To address this, Josef Penninger at the University of British Colombia and Reiner Wimmer at the Institute for Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), together with their colleagues, developed a way to use human pluripotent stem cells to grow self-organizing three-dimensional human blood vessel ‘organoids’ that mimic the structure and function of human blood vessels.

These organoids, which were grown in a Petri dish in the lab, were then transplanted into mice, where they developed into stable, functional blood vessels, including capillaries and even arteries.

“What is so exciting about our work is that we were successful in making real human blood vessels out of stem cells," says Wimmer. "Our organoids resemble human capillaries to a great extent, even on a molecular level, and we can now use them to study blood vessel diseases directly on human tissue."