Inside, blood vessels are lined with a single layer of cells. On their surface, these cells bear specific adhesive proteins by means of which they stick close to each other. Normally, this ensures a perfect sealing of the blood vessels.
The most important adhesive protein is the so-called VE-cadherin. It can be destabilised due to different pathological conditions, e.g. due to a sepsis when bacteria have penetrated into the bloodstream and spread within the whole body. This infection causes inflammatory processes which involve leaks in the blood vessel lining. Blood plasma leaks which might result in life-threatening organ swellings as well as tissue bleeding.
To date, there is no means to seal hyperpermeable blood vessels. However, this would be very helpful e.g. for treating patients with pulmonary edema or allergy-induced organ swelling.
Here, researchers succeeded in taking a first step forward: they have developed small peptide molecules which increase adhesion between vital VE-cadherin adhesive proteins. Thus, the vascular lining is stabilised against inflammatory stimuli.
The peptide molecules work just like an adhesive. They bridge the adhesive proteins with each other, because they are designed following the example of the structure by means of which the VE-cadherins stick close to each other. They have a crosslinking effect which they deploy as tandem peptides arranged one after the other - similar to a medical strip with two adhesive ends.
"These results offer new approaches for the treatment of vascular hyperpermeability", says Prof. Detlev Drenckhahn. However, it is still a long way to go until an application in humans is possible, because the current structure of the molecules is not suitable for such an application.
MEDICA.de; Source: University of Würzburg