Blood vessel prostheses work best when the biochemical and mechanical properties match reality as much as possible and when they are made of biodegradable material. To this end tissue technologists grow natural vascular wall cells, endothelial cells, in a biodegradable tube made of collagen. According to Professor István Vermes tissue technologists are overly concerned with developing stem cells, necessary to build blood vessels, and not enough with the development of the vascular skeleton or scaffold, serving as a framework for those stem cells. During his address on the acceptance of the office of professor in the Molecular Aspects of Cell and Tissue Technology (on 11 april 2002) Vermes gave his vision on the bio-engineering of blood vessels. Besides professor at the University of Twente (The Netherlands) Vermes is doctor-clinical chemist and educator in the regional hospital Medisch Spectrum Twente in Enschede, and special professor in Laboratory Medicine at the Semmelweis Medical University in Budapest.
According to Vermes the key to successful development of artificial human tissue and organs lies in the structure and composition of the porous framework on which cells grow. "The traditional method starts with the development of a prosthesis made of artificial materials. I am concerned with bio-engineering a blood vessel, with biological materials as starting point. To this end we have to imitate all the natural functions of a vessel, including those of the scaffold with all functional biological materials such as growth factors. The skeleton has many more functions than just attaching and keeping cells together. It contains information in the shape of growth factors, cytokines and surface-properties for the growth and development of cells. The chemistry, the shape and way in which it moves under the influence of stress are of vital importance to influencing the behaviour of cells. The skeleton emits signals that are passed on to the inside of the cell via receptors on the cell surface.“ The future of the stem cell, how it develops or dies because of apoptosis, is dependent on the information coming from the vascular skeleton.
A blood vessel is built up, from the inside out, of six different layers of successively endothelial cells, elastic layers of among them smooth muscle cells with around them connective tissue with lymph vessels and nerves. Vermes: "Endothelial cells are important in translating changes in the blood through the production of materials that in turn take care of the balance between blood and the surrounding tissue. To understand the function of these cells in the blood vessel and for the production of the artificial vessel, we study this process by directing ourselves towards cell division (proliferation) and cell death (apoptosis) of endothelial cells." Vermes` strategy is to grow stem cells that differentiate themselves selectively to smooth muscle cells and endothelial cells, and developing a scaffold in the shape of a porous tube of biodegradable and flexible polymers. The stem cells are seeded in the skeleton in the presence of, among others, growth factors.
Bernadette Koopmans | alphagalileo
Molecular microscopy illuminates molecular motor motion
26.07.2017 | Penn State
New virus discovered in migratory bird in Rio Grande do Sul, Brazil
26.07.2017 | Fundação de Amparo à Pesquisa do Estado de São Paulo
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
26.07.2017 | Physics and Astronomy
26.07.2017 | Life Sciences
26.07.2017 | Earth Sciences