Key Discovery in Hepatitis C Research

[Guest guest]

Key Discovery in Hepatitis C Research

2006-12-26 19:01:10

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. 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.

http://www.ccnmag.com/news.php?id=4682

_________________________________________________________________

Dave vs. Carl: The Insignificant Championship Series.  Who will win?

http://clk.atdmt.com/MSN/go/msnnkwsp0070000001msn/direct/01/?href=http://davevsc\

arl.spaces.live.com/?icid=T001MSN38C07001

[Guest guest]

Key Discovery in Hepatitis C Research

2006-12-26 19:01:10

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. 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.

http://www.ccnmag.com/news.php?id=4682

_________________________________________________________________

Dave vs. Carl: The Insignificant Championship Series.  Who will win?

http://clk.atdmt.com/MSN/go/msnnkwsp0070000001msn/direct/01/?href=http://davevsc\

arl.spaces.live.com/?icid=T001MSN38C07001

[Guest guest]

Key Discovery in Hepatitis C Research

2006-12-26 19:01:10

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. 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.

http://www.ccnmag.com/news.php?id=4682

_________________________________________________________________

Dave vs. Carl: The Insignificant Championship Series.  Who will win?

http://clk.atdmt.com/MSN/go/msnnkwsp0070000001msn/direct/01/?href=http://davevsc\

arl.spaces.live.com/?icid=T001MSN38C07001

[Guest guest]

Key Discovery in Hepatitis C Research

2006-12-26 19:01:10

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. 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.

http://www.ccnmag.com/news.php?id=4682

_________________________________________________________________

Dave vs. Carl: The Insignificant Championship Series.  Who will win?

http://clk.atdmt.com/MSN/go/msnnkwsp0070000001msn/direct/01/?href=http://davevsc\

arl.spaces.live.com/?icid=T001MSN38C07001