Viral protein mimic keeps immune system quiet

January 20, 2011

In a new paper published Jan. 21 in the journal Science, a team of researchers led by Microbiology and Immunology professor Blossom Damania, PhD, has shown for the first time that the Kaposi sarcoma virus has a decoy protein that impedes a key molecule involved in the human immune response.

The work was performed in collaboration with W.R. Kenan, Jr. Distinguished Professor, Jenny Ting, PhD. First author, Sean Gregory, MS, a graduate student in UNC's Department of Microbiology and Immunology played a critical role in this work.

The virus-produced protein, called a homolog, binds to the cellular that normally triggers an , a key immune system weapon for fighting viral infection. However, the homolog lacks a key part of the that triggers the inflammation process. Inflammasome activation leads to the production of proinflammatory cytokines and eventual cell death.

Damania compares the homolog's action to what can happen when completing a jigsaw puzzle. "Sometimes there will be a piece that 'almost' fits into an available space, but because it's not an exact fit, leaving it there will keep you from completing the puzzle. The viral homolog gums up the works, preventing the formation of a large complex called the inflammasome, and keeping the cell's immune response from deploying."

According to Damania, a cell's response to a viral invader is to commit suicide. The cells die rather than spread the virus, which uses the cell by hijacking its to produce more virus. Kaposi sarcoma virus' ability to evade the body's immune system helps it lie dormant and persist in the body over a lifetime.

Both researchers are members of UNC Lineberger Comprehensive Cancer Center. Dr. Damania studies the Kaposi's sarcoma virus, which is known to cause certain types of human cancer, because it can infect cells and lie dormant without triggering cellular death. Virus-infected then proliferate, and can give rise to cancer.

Explore further: Major Kaposi's sarcoma discovery announced

Related Stories

Penn researchers discover new mechanism for viral replication

August 16, 2007

Researchers at the University of Pennsylvania School of Medicine have identified a new strategy that Kaposi’s Sarcoma Associated Herpesvirus (KSHV) uses to dupe infected cells into replicating its viral genome. This allows ...

DNA damage response confers a barrier for viral tumorigenesis

September 28, 2007

Kaposi’s sarcoma herpesvirus (KSHV) is a human tumor virus and an etiological agent for Kaposi’s sarcoma (KS). KSHV infection is endemic in sub-Saharan Africa where KS is nowadays the most common malignancy, due to widespread ...

Scientists tackle viral mysteries

June 29, 2009

Scientists know that some cancers are triggered by viruses, which take over cellular systems and cause uncontrolled cell growth. Doctors - and patients who get shingles late in life - have also known for many years that ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.