Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New receptor found on scavenger cells

24.08.2017

Scientists demonstrate how adenovirus invades the immune system of mice

Adenoviral infections have a mild disease progression in healthy people, but it can be dangerous for immunocompromised people. If a patient is infected with the virus and gets a bacterial infection on top of it, it can lead to an excessive inflammatory response known as a cytokine storm, an overreaction by the immune system leading to high concentrations of proteins that promote inflammation.


Images taken with a fluorescence microscope show that the adenovirus can infect macrophages that have the receptor MARCO (left). If MARCO is not present, however, the virus cannot attack the scavenger cells (right).

Source: Marina Freudenberg, Mareike Maler

Many patients do not survive this crisis. Mareike Maler from the University Hospital Freiburg, Prof. Dr. Marina Freudenberg from the Department of Pneumology at the University Hospital Freiburg and the BIOSS Centre for Biological Signalling Studies, Dr. György Fejer from the University of Plymouth, England along with Prof. Dr. Wolfgang Schamel from the Department of Biology and the BIOSS Centre for Biological Signalling Studies have now identified an important adenovirus receptor in macrophages of mice.

The receptor “MARCO“ enables the adenoviruses to invade macrophages, important immune cells responsible for detecting and destroying pathogens. The findings of this study, in which immunologists from the MPI of Immunobiology and Epigenetics Freiburg, RWTH Aachen and the University of Zurich, Switzerland were also involved, have recently been published in the scientific journal mBio.

Previous studies with epithelial cells from skin and gland tissue showed that the viruses bind to the cell-surface proteins called integrins and to CAR, the receptor for coxsackievirus and adenovirus. Biologists have been searching for the adenovirus receptor in immune cells since the 1990s. The research in Freiburg sought to clarify how adenoviruses attack cells of the immune system; that is, on which receptors the viruses on the cellular surface land, in order to invade the cell.

The clarification of this question is of particular interest because the pharmaceutical industry has recently shown interest in using adenoviruses in gene therapy to channel genetic information into human cells. During the first clinical trials, however, some patients showed symptoms of a cytokine storm, suggesting that they may have contracted a bacterial infection.

Up to now, the scavenger receptor MARCO was viewed mainly as a so-called pattern recognition receptor with which the macrophage recognizes bacteria. However, the new findings prove that the receptor has an additional function in fighting viral pathogens. MARCO is probably fundamental for activating macrophages, for instance, in order to produce inflammation-promoting cytokines.

In addition, the researchers demonstrate that macrophages derived from bone marrow precursor cells are far less infected with the virus than the macrophages in the lung. The reason for this is partly because the bone marrow macrophages usually lack MARCO and therefore cannot effectively be attacked by the virus.

After the discovery of these scientific findings, it is now time to conduct testing on humans. Although the receptor MARCO is also found in humans, it is still not clear if the virus interacts with the same receptor in humans. Nonetheless, the study has provided information on how macrophages fight viruses and that they have the potential to activate a cytokine storm in humans. In the future, medication could be used to block the receptor MARCO, thereby avoiding the cytokine storm.

Marina Freudenberg has been researching the activation of macrophages since 1972. Since 2013, she has been working in Wolfgang Schamel’s department in the Department of Biology at the BIOSS Centre for Biological Signalling Studies and at the Department of Pneumology, University of Freiburg. Mareike Maler, the study’s first author, was a graduate student and György Fejer research scientist under Marina Freudenberg. Maler is currently pursuing her doctoral degree in the working group under Prof. Dr. Stefan Martin at the Department of Dermatology at the University Hospital Freiburg.

Caption:
Images taken with a fluorescence microscope show that the adenovirus can infect macrophages that have the receptor MARCO (left). If MARCO is not present, however, the virus cannot attack the scavenger cells (right).

Original publication:
Mareike D. Maler, Peter J. Nielsen, Nicole Stichling, Idan Cohen,
Zsolt Ruzsics, Connor Wood, Peggy Engelhard, Maarit Suomalainen,
Ildiko Gyory, Michael Huber, Joachim Müller-Quernheim, Wolfgang W. A. Schamel, Siamon Gordon, Thilo Jakob, Stefan F. Martin,
Willi Jahnen-Dechent, Urs F. Greber, Marina A. Freudenberg, György Fejer. 2017, Key Role of the Scavenger Receptor MARCO in Mediating Adenovirus Infection and Subsequent Innate Responses of Macrophages. mBio, 8 (4): e00670-17.

For more information about BIOSS:
http://www.bioss.uni-freiburg.de

Kontakt:
Prof. Dr. Marina Freudenberg
Department of Pneumology
University Hospital Freiburg
BIOSS Centre for Biological Signalling Studies
Tel.: 0761/203-67510
E-Mail: marina.freudenberg@biologie.uni-freiburg.de

Weitere Informationen:

https://www.pr.uni-freiburg.de/pm-en/2017/new-receptor-found-on-scavenger-cells

Rudolf-Werner Dreier | idw - Informationsdienst Wissenschaft

More articles from Life Sciences:

nachricht Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University

nachricht Researchers discover specific tumor environment that triggers cells to metastasize
22.11.2017 | University of California - San Diego

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

UCLA engineers use deep learning to reconstruct holograms and improve optical microscopy

22.11.2017 | Medical Engineering

Watching atoms move in hybrid perovskite crystals reveals clues to improving solar cells

22.11.2017 | Materials Sciences

New study points the way to therapy for rare cancer that targets the young

22.11.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>