Featured Research

from universities, journals, and other organizations

Infection warning system in cells contains targets for antiviral and vaccine strategies

Date:
July 30, 2012
Source:
University of Washington
Summary:
Scientists seeking to help the body better defend itself against hepatitis C, West Nile, and other serious virus infections are studying pattern recognition molecules inside living cells, called RIG-I-like receptors. When these receptors detect virus invasions, they alert the immune system to fight infection. Scientists have discovered ways certain proteins interact with RIG-I receptors to more efficiently emit signals in response to viral threats and to recruit killer T-cells. Therapeutics might be designed to mimic these actions.

Two new targets have been discovered for antiviral therapies and vaccines strategies that could enhance the body's defenses against such infectious diseases as West Nile and hepatitis C. The targets are within the infection warning system inside living cells.

Related Articles


No vaccines exist for the viruses that cause West Nile or hepatitis C. New therapies are urgently needed to prevent and treat serious infections by these and related viruses.

The University of Washington is engaged in a major, multipronged effort to design therapeutics that harness the warning signals the body produces when viruses attack. Such therapies would prod people's cells into launching a stronger counterattack to control infections by elusive viruses.

UW specialists in how the body fends off viral diseases are studying pattern recognition molecules, called RIG-I-like receptors, found inside living cells. When these receptors detect virus invasions, they call in the immune system to fight infection.

Scientists in the laboratory of Dr. Michael Gale, Jr., UW professor of immunology, observed an interaction between these molecular dispatchers and a protein called 14-3-3 epsilon This protein acts a docking station where other proteins can gather. There they can more efficiently send out signals in response to threats.

The researchers noticed that the interaction between the alert trigger (RIG-I) and the docking station (14-3-3 epsilon) steps up when cells were infected with virus. The agitation prompts RIG-I to work with other proteins, such as TRIM25. Those proteins are essential for RIG-I to warn the immune system to respond to a virus intruder.

"Our work also demonstrated that RIG-I binding to 14-3-3 epsilon is important for RIG-I to move from within the cell where it detects viral RNA to a location on the cell's membrane where the cell's antiviral defenses can be activated," said Dr. Helene Liu, a postdoctoral fellow who led the study. The move is somewhat like running from the inner corridors of a building to a window to call for help.

"By understanding the molecular partners and location changes that RIG-I requires to convey its signal that virus is present in a cell, we can start to design therapeutics that can trigger this process to kick-off an antiviral immune response and fight virus infection," Liu said.

The scientists reported these initial findings in the May 17 issue of Cell Host & Microbe. The Gale laboratory reports additional observations on the RIG-I-like receptors in the August issue of Immunity, published online July 26.

Postdoctoral fellows Dr. Mehul Suthar and Dr. Hilario Ramos found that, during West Nile virus infection, an RIG-I like receptor called LGP2 promotes the survival and activity of CD8+ T white blood cells, commonly called killer T cells. These disease-fighters eliminate virus-infected cells from the body.

"By increasing the ability and length of time CD8+T cells can work within the body when West Nile virus is present, the immune system is strengthened and has a better chance of eliminating the virus," Suthar commented. Ramos added, "Based on this work, we can consider new ways to boost vaccine effectiveness through design of adjuvants or immune-stimulants. These might be applied within a vaccine approach to regulate LGP2 to enhance immunity to infection."

Gale directed the research effort for both projects. He heads the Center for Study of Innate Immunity to Hepatitis C Virus and the Center for Immune Mechanisms of Flavivirus Control, as well as two National Institutes of Health-funded multi-million dollar programs to develop new antiviral therapies and vaccine adjuvants.

"These two new discoveries," Gale said, "greatly advance our knowledge of how the body senses and responds to virus infection and provide us with new avenues to explore when designing antiviral therapies and new vaccines.

"West Nile virus is an emerging virus that has spread across the United States, and hepatitis C virus infects over 170 million people globally. Both viruses are devastating to the health of the individuals they infect. That is why the development of new clinical resources such as vaccines and antivirals for each is so critical."

West Nile virus is spreading throughout North America through infected mosquitoes. It can cause paralysis and death in people. Hepatitis C virus is transmitted through contact with blood or blood products containing the virus. It causes swelling and inflammation of the liver.

Most hepatitis C infections are persistent because the virus evades the immune defenses that normally limit the course of disease. The virus generates a chronic liver inflammation which scars the organ's tissues. The scarring can lead to liver failure and increases the risk of liver cancer. While therapies are available to treat hepatitis C infections, these treatments have harsh side-effects and are not effective in all people. No antiviral therapies are available to treat people infected with West Nile virus.


Story Source:

The above story is based on materials provided by University of Washington. Note: Materials may be edited for content and length.


Journal Reference:

  1. MehulS. Suthar, HilarioJ. Ramos, MargaretM. Brassil, Jason Netland, CraigP. Chappell, Gabriele Blahnik, Aimee McMillan, MichaelS. Diamond, EdwardA. Clark, MichaelJ. Bevan, Michael Gale. The RIG-I-like Receptor LGP2 Controls CD8 T Cell Survival and Fitness. Immunity, 2012; DOI: 10.1016/j.immuni.2012.07.004

Cite This Page:

University of Washington. "Infection warning system in cells contains targets for antiviral and vaccine strategies." ScienceDaily. ScienceDaily, 30 July 2012. <www.sciencedaily.com/releases/2012/07/120730141630.htm>.
University of Washington. (2012, July 30). Infection warning system in cells contains targets for antiviral and vaccine strategies. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2012/07/120730141630.htm
University of Washington. "Infection warning system in cells contains targets for antiviral and vaccine strategies." ScienceDaily. www.sciencedaily.com/releases/2012/07/120730141630.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.S. Ebola Response Measures Demonstrated

U.S. Ebola Response Measures Demonstrated

AP (Oct. 31, 2014) Officials in the Washington area showed off Ebola response measures being taken at Dulles International Airport and the National Institutes of Health. (Oct. 31) Video provided by AP
Powered by NewsLook.com
Fauci Says Ebola Risk in US "essentially Zero"

Fauci Says Ebola Risk in US "essentially Zero"

AP (Oct. 30, 2014) NIAID Director Anthony Fauci said the risk of Ebola becoming an epidemic in the U.S. is essentially zero Thursday at the Washington Ideas Forum. He also said an Ebola vaccine will be tested in West Africa in the next few months. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Nurse Defies Ebola Quarantine With Bike Ride

Nurse Defies Ebola Quarantine With Bike Ride

AP (Oct. 30, 2014) A nurse who vowed to defy Maine's voluntary quarantine for health care workers who treated Ebola patients followed through on her promise Thursday, leaving her home for an hour-long bike ride. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Pot-Infused Edibles Raise Concerns in Colorado

Pot-Infused Edibles Raise Concerns in Colorado

AFP (Oct. 30, 2014) Colorado may have legalized marijuana for recreational use, but the debate around the decision still continues, with a recent - failed - attempt to ban cannabis-infused edibles. Duration: 01:53 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins