Scientists at the University of Tübingen discover new mechanism that supports our immune system during sleep
Getting enough sleep is vital to supporting our immune system in fighting off pathogens – so much is common knowledge. But what we don't know is how exactly sleep affects certain immune functions. Scientists at the University of Tübingen and the University of Lübeck have now discovered a new mechanism by which sleep supports the immune system.
The team led by Dr. Luciana Besedovsky and Dr. Stoyan Dimitrov from the Institute of Medical Psychology and Behavioral Neurobiology in Tübingen and Dr. Tanja Lange from the Clinic for Rheumatology and Clinical Immunology in Lübeck were able to show that the function of T cells, the white blood cells that are responsible for combating pathogens, was impaired after only three hours without sleep. The study was published in the Journal of Experimental Medicine.
The scientists conducted a 24-hour experiment with volunteers: One group was allowed to sleep for eight hours at night, a second group stayed awake for the whole period. During the experiment, blood was regularly taken from the participants. In particular, the research team examined the binding strength of T cells to a molecule named ICAM-1 (intercellular adhesion molecule-1), which enables them to attach to other cells, in a process known as adhesion.
This is important for their function: "T cells circulate constantly in the bloodstream looking for pathogens. Adhesion to other cells enables them to migrate to different areas in the body and, for example, dock onto infected cells in order to subsequently kill them," says Stoyan Dimitrov, first author of the study. As the study shows, the adhesion of T cells was significantly reduced in sleep deprived subjects.
In order to further investigate how sleep affects T-cell function, plasma – the part of the blood that contains soluble substances such as hormones – was taken from sleeping and sleep deprived subjects. This plasma was applied to isolated T cells for a few minutes. Plasma taken from sleep deprived subjects reduced the adhesion significantly compared to the plasma from subjects who had slept.
In another experiment, the team was able to reverse this suppression of T-cell function by blocking Gαs-coupled receptors. Amongst other substances, the stress hormone adrenaline and prostaglan-dins, which play a role in inflammation, bind via these receptors. "This shows that even following brief sleep deprivation soluble molecules activate these receptors and thereby impair the adhesion of the T cells," says Luciana Besedovsky, head of the study.
In parallel experiments, the researchers were also able to show that some of the soluble molecules that bind to this receptor class, such as adrenaline, prostaglandins and the neuromodulator adeno-sine, strongly impair adhesion when administered directly to T cells. The same substances are also strongly elevated in a number of pathological conditions, such as chronic stress or cancer.
"This means that our findings also have clinical relevance outside sleep research. They could explain why the immune system is suppressed in some diseases," says Lange. Besedovsky summarizes: "Just three hours without sleep are sufficient to reduce the function of important immune cells. Our results show a potential fundamental mechanism by which sleep helps us fight infection."
University of Tübingen
Institute for Medical Psychology and Behavioral Neurobiology
Dr. rer. nat. Luciana Besedovsky
Phone +49 7071 29-88928
Dr. rer. nat. Stoyan Dimitrov
Phone +49 7071 29-88927
University of Lübeck
Clinic for Rheumatology and Clinical Immunology
Priv.-Doz. Dr. med. Tanja Lange
Phone +49 451 500 75491
Stoyan Dimitrov, Tanja Lange, Cécile Gouttefangeas, Anja T.R. Jensen, Michael
Szczepanski, Jannik Lehnnolz, Surjo Soekadar, Hans-Georg Rammensee, Jan Born
and Luciana Besedovsky: “Gαs-coupled receptor signaling and sleep regulate integrin activation of
human antigen-specific T cells.” Journal of Experimental Medicine:
Antje Karbe | idw - Informationsdienst Wissenschaft
Chip-based optical sensor detects cancer biomarker in urine
06.12.2019 | The Optical Society
Scientist identify new marker for insecticide resistance in malaria mosquitoes
06.12.2019 | Liverpool School of Tropical Medicine
University of Texas and MIT researchers create virtual UAVs that can predict vehicle health, enable autonomous decision-making
In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location...
With ultracold chemistry, researchers get a first look at exactly what happens during a chemical reaction
The coldest chemical reaction in the known universe took place in what appears to be a chaotic mess of lasers. The appearance deceives: Deep within that...
Abnormal scarring is a serious threat resulting in non-healing chronic wounds or fibrosis. Scars form when fibroblasts, a type of cell of connective tissue, reach wounded skin and deposit plugs of extracellular matrix. Until today, the question about the exact anatomical origin of these fibroblasts has not been answered. In order to find potential ways of influencing the scarring process, the team of Dr. Yuval Rinkevich, Group Leader for Regenerative Biology at the Institute of Lung Biology and Disease at Helmholtz Zentrum München, aimed to finally find an answer. As it was already known that all scars derive from a fibroblast lineage expressing the Engrailed-1 gene - a lineage not only present in skin, but also in fascia - the researchers intentionally tried to understand whether or not fascia might be the origin of fibroblasts.
Fibroblasts kit - ready to heal wounds
Research from a leading international expert on the health of the Great Lakes suggests that the growing intensity and scale of pollution from plastics poses serious risks to human health and will continue to have profound consequences on the ecosystem.
In an article published this month in the Journal of Waste Resources and Recycling, Gail Krantzberg, a professor in the Booth School of Engineering Practice...
03.12.2019 | Event News
15.11.2019 | Event News
15.11.2019 | Event News
06.12.2019 | Earth Sciences
06.12.2019 | Life Sciences
06.12.2019 | Information Technology