Human veins bred in the laboratory - stem cell research wants to make diabetes curable

For the first time, researchers are breeding human blood vessels without bodies

An Austrian research team reports on a completely new approach to curing diabetes and other chronic diseases. For the first time, the researchers succeeded in breeding functional human blood vessels, ie veins, from stem cells in the laboratory. The team wants to gain new insights into diabetes, cancer and other vascular diseases.

In recent years, stem cell research has repeatedly shown that it is possible to grow organs or cells from stem cells. Such cultured organs are called in the jargon vascular organoids. Researchers at the Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA) have now succeeded in breeding a network of functional human blood vessels from stem cells. Such vein systems without body should allow completely new studies that could make vascular diseases curable. The study results were recently published in the renowned journal "Nature".

Research breakthrough or ethics overrun?

The IMBA team speaks of a milestone in stem cell research. The so-called blood vessel organoids from the laboratory should become an important driver in basic research. Because the bred human vein systems reflect according to the researchers processes of organ development and disease in humans. Thanks to such systems can be vascular diseases such as diabetes first "replay" in the laboratory. "Our organoids are incredibly similar to human capillaries and allow us, for the first time, to study blood vessel diseases directly on human tissue," Reiner Wimmer, the lead author of the current study, said in a press release.

New therapies for vascular diseases are needed

The human blood vessels cover the body like a fine mesh and not only reach all the organs. The smallest veins, the so-called capillaries, are only a few microns in size and provide each individual cell of the body with vital nutrients and oxygen. As the researchers report, abnormal changes in the blood vessels, as is the case with diabetes, are increasing worldwide. Meanwhile, about 420 million people are affected. People who suffer from diabetes also have an increased risk of serious secondary diseases such as kidney failure, blindness, heart attacks, strokes and amputations. With the numbers rising, the research team expects more effective therapies to be developed.

What role do the capillaries play in diabetes?

According to the researchers, the first disease process takes place in the tiny branches of the capillaries. The outer wall of these vessels is encased in so-called basement membranes, which support the capillaries. These membranes are massively increased in diabetes patients, whereby the nutrient and oxygen supply is considerably limited. This often leads to the death of the small blood vessels.

Bred vascular diseases

The cultured blood vessel organoids from the laboratory make it possible for the first time to simulate such disease processes on "real" blood vessels. The researchers led a nutrient medium with high sugar content and inflammatory substances through the vessels. "Surprisingly, we were able to observe the typical thickening of the basal membrane in diabetic organoids," says Wimmer.

Drug test with a difference

In further experiments, the researchers tested how the diabetic blood vessels reacted to current diabetes medications. However, most drugs did not show any effects. However, the team identified two molecules (Notch3 and Dll4) that significantly regulate the thickening of the capillary basement membrane. A review of human diabetes patients also showed that they had increased Notch3 activity. Blocking these signaling pathways could be a new approach to treating diabetes, the research team suggests.

Even new findings in Alzheimer's and cancer possible

"At the same time, blood vessels also play a key role in the progression of cancer or Alzheimer's disease," adds Josef Penninger, the founding director of the IMBA. Every single organ in our organism is connected to the circulatory system. With the development of blood stem organoids from stem cells, the team has created an important model system for biomedicine, the researchers said. (Vb)