The motivation for the award states that “His research has been of essential significance for our understanding of how blood-vessel cells cooperate to achieve the functional balance required to maintain efficient blood circulation”.

“It was surprising, gratifying and flattering. I am grateful to the person or persons who nominated me and to the prize committee that selected me, in what I am convinced was extremely tough competition. I can name many researchers in the Nordic countries who deserve this prize more than I do, in my opinion”, says Christer Betsholtz.

Significant research breakthrough

Christer Betsholtz is a leading vascular researcher and has charted the communication between different types of cells in the blood-vessels and studied how they develop and form. Two types of cells particularly captured his interest: endothelial cells, which form the inner tube of our blood-vessels, and pericytes, a cell type included in all blood capillaries, which are the body’s smallest blood vessels.
Christer Betsholtz is behind the unexpected discovery that pericytes play a fundamental role in blood-vessel growth and function, and in recent years his research team has focused particularly on the role of pericytes in the brain. Another significant research breakthrough was the discovery of a special type of endothelial cell, which guides newly-formed blood-vessels in the body.

“When blood-vessels elongate and branch off, the process is roughly the same as for a branchlet on a tree. We could see that at the tip of each blood-vessel sprout is a specialised endothelial cell, known as a tip cell. The tip-cells in turn extend a brush of thread-like structures that sense different molecules in the surroundings and steer the blood-vessels’ elongation in the right direction. We also discovered how new tip cells are formed when blood vessels branch off." 

Since the discovery of the roles of pericytes and tip cells in the new formation of blood-vessels, the research community’s interest has increased considerably and the cells are now being intensively studied from both health and disease perspectives, including cancer and Alzheimer’s disease.

Christer Betsholtz is currently working in both these areas and, among other things, has established that pericytes play an important role in the regulation of the blood-brain barrier – a protective system for the brain’s nerve cells, which need a strictly regulated environment in order to function. The exceptionally dense blood-vessels in the brain only allow the passage of substances that the brain needs such as blood sugar, and exclude others that are potentially harmful to the brain from entering the blood circulation system. This is good in almost all respects, but a challenge arises when the aim is to deliver drugs to the brain to treat these diseases.

“We have produced an experimental model using mice that have very few pericytes in the brain and have seen that their blood-brain barrier opens a special route into the brain”, says Christer Betsholtz, who hopes the model will be used in future drug development.

Part of his research now concerns the production of a molecular mapping of the cells that make up the brain’s blood-vessels. The first version was published in 2018 and is currently used by researchers worldwide. He hopes the map will contribute to an increased understanding of blood-vessels’ role in different diseases, and that it will also provide keys that will help researchers open the blood-brain barrier for the delivery of drugs.