Scientists at the Max Planck Institute for Molecular Biomedicine in Münster, Germany, have developed a synthetic tissue in which blood vessels can form. The most important advance made by the researchers was to have been able to delve into the specific qualities of the materials: in this way, they were able to determine which aspects or characteristics promote the growth of blood vessels.
The system is based on a three dimensional hydrogel sugar-based. In it, specialists make two channels with an acupuncture needle: they run parallel, separated by a distance of approximately one millimeter. Endothelial cells are incorporated into each of these channels.
The endothelial cells line blood vessels in natural tissues. It is a type of flattened cell that protects the interior of the blood vessels and mainly the capillaries, forming a sector of its wall. One of its functions is to regulate angiogenesis, the physiological process through which new blood vessels are formed from pre-existing vessels.
In the artificially created system, the “cultured” endothelial cells form contacts with each other and adhere to the synthetic tissue environment in the first channel, thus creating a major blood vessel after about a day. But the next step is perhaps the most important: now, researchers must promote the creation of other blood vessels.
Molecules that activate the process
According to a Press release, the scientists incorporated into the culture molecules that drive blood vessel growth in natural tissues, using the second channel created for this. Previously, they had analyzed and studied which were the best conditions and the molecules indicated to favor the development of new blood vessels.
They then confirmed that the endothelial cells migrate to the hydrogel thanks to the impulse of the incorporated molecules. This step is crucial so that they can form tubular structures and develop new blood vessels, which connect to the main vessel.
An obstacle overcome
Although tubular structures developed, they were smaller than those present in natural tissues. However, as established in the conclusions of the study, published in the journal Nature Communications, the specialists managed to overcome this stumbling block, in an advance that enhances the potential of this research.
The problem was in the interaction between certain molecules and the sugar that makes up the hydrogel.
By exchanging these molecules, they were able to make the endothelial cells migrate faster towards the hydrogel and develop suitable tubular structures. Finally, blood vessels were formed according to conditions similar to natural ones.
A set of hits
In conclusion, scientists believe that the keys to the success of this tissue Synthetic is the ability to activate certain adhesion molecules on the membrane of endothelial cells that create blood vessels, allowing them to integrate and migrate in groups from the main vessel, forming tubular structures.
At the same time, the conditions of the material used in the synthetic hydrogel allowed the cells to form blood vessels of adequate size.
A basic condition for a tissue to be functional is that blood vessels can grow in it and connect with the body’s vascular system, ensuring that the tissue receives the necessary supply of oxygen and nutrients.
Considering that the new synthetic fabric seems to achieve this goal, it could become a first step for the development of replacement artificial functional organs, with wide applications in regenerative medicine and other related fields.
Synthetic extracellular matrices with tailored adhesiveness and degradability support lumen formation during angiogenic sprouting. Liu J, Long H, Zeuschner D, Räder AFB, Polacheck WJ, Kessler H, Sorokin L and Trappmann B. Nature Communications (2021).DOI:https://dx.doi.org/10.1038/s41467-021-23644-5
Photo: Scientists have succeeded in designing a synthetic hydrogel in which cells form new blood vessels, which grow from a main blood vessel (upright on the left). Credit: Liu et al./Nat Comm 2021.
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.