Someone in Germany suffers a stroke every two minutes. The cause is usually a blockage in the blood vessels that supply the brain. Anyone who survives a stroke may sustain severe disabilities, such as impaired speech or paralyses; the reason being that the brain is damaged because it was deprived of sufficient blood for too long.
The blood vessels tend to be blocked by clotted blood. Dissolving these clots or stopping them from occurring in the first place is the primary objective in the treatment and prevention of strokes.
Consequently, the search for new and better therapies starts where the cause of the illness lies: with the blood coagulation that leads to the formation of clots. The Würzburg scientists were all the more astonished, then, when they made a discovery elsewhere - the T cells of the immune system also play a role in strokes. These are actually the cells responsible for combating pathogens.
T cells have a damaging effect
What exactly did the researchers discover? Mice with no T cells due to a genetic defect suffer less severe strokes than their normal fellow mice. What is more, they develop fewer symptoms of neurological deficiencies, such as paralyses, after a stroke. This means that T cells have a negative effect on the progression of a stroke. This has been proven by the working groups of Guido Stoll, Christoph Kleinschnitz, and Heinz Wiendl from the university's Department of Neurology together with Bernhard Nieswandt from the Rudolf Virchow Center for Experimental Biomedicine.
"The fact that T cells have such a damaging effect in the case of acute strokes came as a complete surprise to us," reports Christoph Kleinschnitz. The adverse effect can be traced back to two sub-groups of immune cells, the so-called CD4- and CD8-positive T helper cells.
But do the T cells intensify a stroke? The Würzburg scientists were able to rule out two possible mechanisms in their experiments. Firstly, the T cells do not promote the agglutination of the blood platelets or, therefore, the formation of blood clots. "Secondly, they do not fuel the process either in the form of a specific immune reaction," says neuroimmunologist Heinz Wiendl. Further research is now needed to clarify how the T cells exercise their damaging effect.
New approaches to therapy conceivable
The Würzburg researchers hope that their work will help improve stroke therapy for humans. If the findings can be transferred to people, it might be possible to devise new approaches by purposefully manipulating the T cells. It is conceivable, for example, that in the early stages of a stroke the harmful fraction of the T cells may be deactivated temporarily to thereby reduce the symptoms of deficiencies. "But further studies are needed before we reach that point," says neurologist Guido Stoll.
Results achieved in two collaborative research centers
These research findings have been made in the Würzburg collaborative research centers 688 and 581. Both are funded by the German Research Foundation (DFG). The results now are published in the online issue of Blood, the Journal of the American Society of Hematology.
Christoph Kleinschnitz, Nicholas Schwab, Peter Kraft, Ina Hagedorn, Angela Dreykluft, Tobias Schwarz, Madeleine Austinat, Bernhard Nieswandt, Heinz Wiendl, and Guido Stoll: "Early detrimental T cell effects in experimental cerebral ischemia are neither related to adaptive immunity nor thrombus formation." Blood First Edition Paper, prepublished online March 9, 2010; DOI 10.1182/blood-2009-10-249078
Dr. Christoph Kleinschnitz, T +49 (0)931 201-23765, firstname.lastname@example.org
Robert Emmerich | idw
Improving memory with magnets
28.03.2017 | McGill University
Graphene-based neural probes probe brain activity in high resolution
28.03.2017 | Graphene Flagship
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
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...
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...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
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...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Life Sciences
28.03.2017 | Information Technology
28.03.2017 | Physics and Astronomy