Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study identifies protein essential for immune recognition, response to viral infection

25.11.2013
Mice lacking GEF-H1 protein expression unable to mount immune defense against influenza

A Massachusetts General Hospital (MGH)-led research team has identified an immune cell protein that is critical to setting off the body's initial response against viral infection.

The report that will be published in an upcoming issue of Nature Immunology and is receiving early online release describes finding that a protein called GEF-H1 is essential to the ability of macrophages – major contributors to the innate immune system – to respond to viral infections like influenza.

"The detection of viral genetic material inside an infected cell is critical to initiating the responses that signal the immune system to fight an infection and prevent its spread throughout the body," says Hans-Christian Reinecker, MD, of the Center for the Study of Inflammatory Bowel Disease in the MGH Gastrointestinal Unit, senior author of the report. "Our findings indicate that GEF-H1 may control immune responses against a wide variety of RNA and DNA viruses that pose a threat to human health."

The body's first line of defense against infection, the innate immune system rapidly responds to invading pathogens by mobilizing white blood cells, chemical factors called cytokines and antimicrobial peptides. When viruses invade cells, they often move towards the nucleus in order to replicate and sometimes to integrate their own genetic material into that of the host cell, traveling along structures called microtubules that cells use for internal protein transport. But how microtubule-based movement of viral components contributes to induction of the immune response has been unknown.

GEF-H1 is known to bind to microtubules, and previous research indicated that it has a role in immune recognition of bacteria. A series of experiments by Reinecker's team found that GEF-H1 is expressed in macrophages – key components of the innate immune system – and activated in response to viral RNA and that it controls the expression of beta interferon and other cytokines. Mice in which expression of GEF-H1 was knocked out were unable to mount an effective immune response to influenza A and to encephalomyocarditis, a virus that causes several types of infection in animals.

"The sensing of intracellular viral nucleic acids for induction of interferons is so important that many viruses, including influenza A, have evolved specific strategies to interfere with activation of the interferon defense system," says Reinecker, an associate professor of Medicine at Harvard Medical School. "We are hopeful that this discovery will allow the development of new strategies to curtail viral mechanisms that impede the immune responses to infections that are often associated with high mortality rates."

The co-lead authors of the Nature Immunology report are Hao-Sen Chiang, PhD, and Yun Zhao, MD, PhD, MGH Gastrointestinal Unit. Additional co-authors are Joo-Hye Song, PhD, Song Liu, MD, Megha Basavappa and Kate Jeffrey, PhD, MGH Gastrointestinal Unit; Ninghai Wang, MD, PhD, and Cox Terhorst, Beth Israel Deaconess Medical Center; and Arlene Sharpe, MD, PhD, Harvard Medical School. The study was supported by National Institutes of Health grants AI093588, DK-068181, DK-033506, 630 DK-043351 and DK-52510.

Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $775 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, reproductive biology, systems biology, transplantation biology and photomedicine.

Sue McGreevey | EurekAlert!
Further information:
http://www.massgeneral.org/

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>