Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New findings challenge view of key part of immune defense

02.03.2011
The natural killer cells of our immune defense are activated for an extended period after the acute infection, which challenges the prevailing view that the elevation and activation of cells quickly pass. This is shown in a study regarding vole fever that was recently published by researchers at Umeå University, Sweden in Journal of Experimental Medicine.

These are findings of a years-long project where patients with vole fever, a northern Swedish hemorrhagic fever that has been studied with regard to natural killer (NK) cells. Vole fever is a common infection in northern Sweden that is caused by a hantavirus, Puumala virus, which is prevalent in bank voles and infects humans primarily via inhalation of virus-contaminated dust.

The symptoms are primarily high fever, head and muscle pain, abdominal pain, and generally impacted condition. Involvement of the kidneys and lungs are common. There is no dedicated and effective treatment today. As vole fever is a hemorrhagic fever, there is often a pronounced reduction in blood platelets, and bleeding complications occur. Some 30 % of the diagnosed cases are hospitalized. Mortality is 0.5 % owing to bleeding, shock, and multiple organ failure.

The Umeå researchers, led by assistant professor Clas Ahlm, have used a unique patient cohort to study the expansion of NK cells and their activity in the course of the infection in collaboration with scientists at the Karolinska institute. The material was gathered during and following the major outbreak of vole fever in 2007. There have been few previous studies of NK cells in acute viral infections in humans, even though they are regarded as part of our so-called innate immunity. The Puumala virus itself is not cytopatogenic, i.e. doesn’t kill the infected cells. The Umeå scientists’ hypothesis is therefore that part of the pathological mechanism in vole fever involves the immune defense against the virus infection, which is further supported by these findings.

The study revealed an expansion of NK cells. This expansion persisted for an extended period after the acute infection, which surprised the researchers. This finding challenges to some extent the previous view that the elevation and activation of NK cells quickly subsides in acute viral infections. The results of the study indicate that some NK cells may have memory-like functions.

Hemorrhagic fevers are best known as exotic diseases with high mortality rates that primarily ravage Africa. They are caused by hantaviruses that often infect humans from animals, so-called zoonos. The Ebola virus is probably the best-known variant. The Marburg virus is another. Viruses that cause hemorrhagic fevers are most often categorized as class 3-4 infectious agents, the class that requires the highest level of security when handled. for more information about this.

For more information, please contact Clas Ahlm, assistant professor at the Department of Clinical Microbiology, infectious diseases, at: +46 (0)90-785 23 09; e-mail clas.ahlm@climi.umu.se

The article “Rapid expansion and long-term persistence of elevated NK cell numbers in humans infected with hantavirus”. (J Exp Med 2011 Jan 17)

A high-resolution portrait picture of Clas Ahlm is found on http://www.umu.se/digitalAssets/65/65144_ahlm_clas_0813_110301_mpn.jpg

Bertil Born | idw
Further information:
http://jem.rupress.org/content/208/1/13
http://f1000.com/7906956

More articles from Life Sciences:

nachricht New catalyst controls activation of a carbon-hydrogen bond
21.11.2017 | Emory Health Sciences

nachricht The main switch
21.11.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Previous evidence of water on mars now identified as grainflows

21.11.2017 | Physics and Astronomy

NASA's James Webb Space Telescope completes final cryogenic testing

21.11.2017 | Physics and Astronomy

New catalyst controls activation of a carbon-hydrogen bond

21.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>