Navigation Links
Molecular ‘On/Off Switch’ Controls Immune Defenses Against Viruss

Much like flipping a light switch, the hepatitis C virus turns on human immune defenses upon entering the body //but also turns off those defenses by manipulating interaction of key cellular proteins, UT Southwestern Medical Center researchers have found.

This same molecular “on/off switch” controls immunity against many viruses, highlighting a potential new target for novel therapeutics to fight viruses, the researchers report.

In a study available online this week and in an upcoming issue of the Proceedings of the National Academy of Sciences, UT Southwestern scientists describe how the proteins RIG-I and LGP2 normally interact to turn on and off immune response to hepatitis C.

It’s known that when a virus invades a cell, the RIG-I protein triggers the body to generate an immune response. Once the virus has been cleared out, the LGP2 protein turns off the RIG-I signals.

This interaction between RIG-I and LGP2 is vital for properly regulating immunity, but viruses such as hepatitis C can disrupt the normal process to shut down immune defenses early, the research team found.

“This knowledge will help us design drugs that mimic the viral effects on these proteins to either activate a host’s immune response or shut it down,” said Dr. Michael Gale, associate professor of microbiology and the study’s senior author. “This holds great potential in developing new disease therapies, because the tactics employed by hepatitis C to trigger immune response are similar to those employed by other viruses such as West Nile, influenza and the common cold.”

Dr. Gale’s research centers on studying the mechanisms viruses use to evade immune defenses. Of particular interest is the hepatitis C virus, a blood-borne infection transmitted by intravenous drug use, blood transfusions and sexual contact. It affects 4 million U.S. residents and is the nation’s leading cause of cirrhosis and liver cancer.

In 2005 Dr. Gale and his team completed several breakthrough studies on hepatitis C, discovering that the RIG-I protein binds to viral genetic material. Then, RIG-I changes its shape and sends signals to other proteins that spur production of interferon, a molecule that stops viral replication. The researchers also found that the virus launches a counterattack on RIG-I, producing a protein called a protease to disrupt the signaling process, preventing interferon production and allowing viral replication.

Just how RIG-I signaling is normally regulated, however, hadn’t been known.

In the current study, UT Southwestern researchers found that RIG-I and LGP2 each contain a repressor domain, a sort of docking site that controls the actions of each protein. The domain is the key site that regulates the ability of RIG-I to bind to its signaling partners, including LGP2, acting as a switch for controlling immune response, Dr. Gale said.

“Hepatitis C and others viruses hijack this signaling pathway to stop immune defenses,” he said.

His research team and others are working to design novel therapeutics and drugs that could mimic viral effects on RIG-I to spur antiviral response or, conversely, mimic viral effects on LGP2 to shut down RIG-I activity. RIG-I shutdown would be necessary in cases when the immune system’s response to a virus is dangerously overactive, which happened in many flu cases during the 1918 pandemic.

“Fine-tuning immune response to infection is where antiviral or immune regulatory drugs are headed,” said Dr. Gale.

SourceNewswise
SRM
'"/>




Related medicine news :

1. Molecular markers for early diagnosis of breast and ovarian cancer
2. Scientists Developed Map For Brain Molecular Communities
3. Molecular Mechanism Of HIV Infecting The Healthy Cells Discovered.
4. Molecular Flaw Detected in Aggressive Breast Cancers
5. Molecular Computer Developed To perform Calculations From Within Human Body
6. Molecular Imaging Of Cancer Now Possible, New Hybrid Virus Produced
7. Molecular Basis Of ALS Found
8. New Molecular Treatment Identified To Treat Blood Cell Cancers
9. Researchers Find Molecular "Brake" to Cell Death
10. Solitons Could Power Molecular Electronics, Artificial Muscles
11. Discovery of Agile Molecular Motors Could Aid in Treating Motor Neuron Diseases
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:10/12/2017)... ... ... Leading pediatric oncology experts at Children’s National Health System will join ... International Society of Paediatric Oncology (SIOP) Oct. 12-15. Chaired by Jeffrey Dome, ... at Children’s National, and Stephen P. Hunger, M.D., Chief of the Division of ...
(Date:10/12/2017)... ... October 12, 2017 , ... Women-owned and ... 2017 Best and Brightest in Wellness® by Best and Brightest. OnSite Wellness will ... Friday, Oct. 20 from 7:30 a.m. to 2 p.m. at the Henry Autograph ...
(Date:10/12/2017)... ... October 12, 2017 , ... ... property taxes a year. In some states—like New York, New Jersey, Massachusetts, Texas, ... many overseas retirement havens have extremely low property-tax rates, which contributes to the ...
(Date:10/12/2017)... D.C. (PRWEB) , ... October 12, 2017 , ... ... Cal Dining at the University of California Berkeley, and other leading institutions in ... the buying power of institutions to change the way animals are raised for ...
(Date:10/12/2017)... ... October 12, 2017 , ... ... its executive staff with the addition of industry sales leader, Thomas (Tom) Slott, ... develop the national distribution and sales network, direct the efforts of the surgical ...
Breaking Medicine News(10 mins):
(Date:10/4/2017)... 2017  According to the Centers for Disease Control and Prevention (CDC), ... PhysicianOne Urgent Care is helping communities across Massachusetts , ... by offering no-cost* flu shots through the end of the month. ... insurance regulations. ... get a flu shot is by the end of October, according to ...
(Date:10/2/2017)... Fla. , Oct. 2, 2017  AllianceRx Walgreens ... company formed by Walgreens and pharmacy benefit manager Prime ... its new brand, which included the unveiling of new ... , as well as at a few other ... the new brand to patients, some of whom will ...
(Date:9/28/2017)... 2017 Cohen Veterans Bioscience and Early Signal ... wearable and home sensors for real-time monitoring of patients ... a nonprofit organization focused on disruptive health solutions for ... analytical system to record and integrate behavioral, cognitive, physiological ... ...
Breaking Medicine Technology: