'On/Off ' Switch Controls Immune Defenses Against Viruses

WEDNESDAY, Dec. 27 (HealthDay News) -- A molecular "on/off" switch that controls immune system response to viruses has been identified by researchers at the University of Texas Southwestern Medical Center at Dallas.

They found that when the hepatitis C virus enters the human body, the virus switches on immune system defenses. But the virus can turn off those defenses by manipulating the interactions of certain cellular proteins called RIG-1 and LGP2.

This same "on/off" switch controls immune system response against many kinds of viruses, and the switch may offer a new target for new drugs to fight viruses, the researchers said.

"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," study senior author Dr. Michael Gale, an associate professor of microbiology, said in a prepared statement.

"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," Gale said.

The study appears in this week's online issue of theProceedings of the National Academy of Sciences.

More information

The American Society for Microbiology has more about viruses.

SOURCE: University of Texas Southwestern Medical Center at Dallas, news release, Dec. 25, 2006