Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Polymer Ribbons for Better Healing

26.07.2013
Freiburg researchers develop hydrogels for tissue regeneration that can be fine-tuned to fit any body part

A new kind of gel that promotes the proper organization of human cells was developed by Prof. Prasad Shastri of the Institute of Macromolecular Chemistry and BIOSS Centre for Biological Signalling Studies Excellence Cluster at the University of Freiburg and BIOSS Centre for Biological Signalling Studies graduate students Aurelien Forget and Jon Christensen in collaboration with Dr. Steffen L¨¹deke of the Institute for Pharmaceutical Sciences.



3-D organization and branching of human endothelial cells into vascular trees in carboxylated agarose gels
© Aurelien Forget, Prasad Shastri

These hydrogels made of agarose, a polymer of sugar molecules derived from sea algae, mimic many aspects of the environment of cells in the human body. They can serve as a scaffold for cells to organize in tissues. In the cover article of the Proceedings of the National Academy of Sciences Prof. Shastri and co-workers show how by applying these hydrogels they could grow blood vessel structures from cells in an unparalleled way. These gels could be used in the future to help damaged tissue heal faster.

The cells environment in the body is composed of collagen and polymers of sugars. It provides mechanical signals to the cells, necessary for their survival and proper organization into a tissue, and hence essential for healing. A gel can mimic this scaffold. However it has to precisely reproduce the molecular matrix outside the cell in its physical properties. Those properties, like the matrices stiffness, vary in the body depending on the tissue.

The team of Prof. Shastri modified agarose gels by adding a carboxylic acid residue to the molecular structure of the polymer to optimally fit the cells environment. Hydrogels form when polymer chains that can dissolve in water are crosslinked. In an agarose gel the sugar chains organize into a spring-like structure. By adding a carboxylic acid to this backbone, the polymers form ribbon-like structures ¨C this allows for the stiffness of the gel to be tuned to adapt the scaffold to every part of the human body.

To demonstrate the versatility of the gel the researchers manipulated endothelial cells that make up vascular tissue to organize into blood vessels outside the body. By combining the appropriate biological molecules found in a developing embryo, they identified a single condition that encourages endothelial cells to form large blood vessel-like structures, several hundred micrometers in height. This discovery has implications in treating damage to heart and muscle tissue.

Prof. Shastri says ¡°it is really remarkable that the organization of the endothelial cells into these free standing vascular lumens occurs within our gels without the need for support cells¡±. It has been long thought the formation of large vessel-like structures requires additional cells called mural support cells, which provide a platform for the endothelial cells to attach and organize.

¡°We were surprised to find that the endothelial cells underwent a specific transformation called apical-basal polarization¡±, adds Prof. Shastri. It turns out that such polarization is necessary for the development of blood vessels and occurs naturally in a developing embryo. The ability to induce this polarization in cells in three-dimensional cultures in a synthetic polymer environment is a unique feature of the new gel.

Original publication:
Aurelien Forget, Jon Christensen, Steffen L¨¹deke, Esther Kohlera, Simon Tobias, Maziar Matloubi, Ralf Thomann, and V. Prasad Shastri. (2013) Polysaccharide hydrogels with tunable stiffness and provasculogenic properties via ¦Á-helix to ¦Â-sheet switch in secondary structure. Proc. Natl. Acad. Sci. USA Vol.110, no 32, doi: 10.1073/pnas.1222880110
Contact:
Prof. Dr. V. Prasad Shastri
Institute of Macromolecular Chemistry and BIOSS Centre for Biological Signalling
University of Freiburg
Phone: 0761/203- 6268
E-Mail: prasad.shastrI@makro.uni-freiburg.de

| University of Freiburg
Further information:
http://www.uni-freiburg.de

More articles from Life Sciences:

nachricht Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory

nachricht How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>