Viral protein mimic keeps immune system quiet

Jan 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: New compounds protect nervous system from the structural damage of MS

Related Stories

Scientists tackle viral mysteries

Jun 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 ...

Penn researchers discover new mechanism for viral replication

Aug 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

Sep 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 ...

Recommended for you

Mystery of the reverse-wired eyeball solved

Feb 27, 2015

From a practical standpoint, the wiring of the human eye - a product of our evolutionary baggage - doesn't make a lot of sense. In vertebrates, photoreceptors are located behind the neurons in the back of the eye - resulting ...

Neurons controlling appetite made from skin cells

Feb 27, 2015

Researchers have for the first time successfully converted adult human skin cells into neurons of the type that regulate appetite, providing a patient-specific model for studying the neurophysiology of weight ...

Quality control for adult stem cell treatment

Feb 27, 2015

A team of European researchers has devised a strategy to ensure that adult epidermal stem cells are safe before they are used as treatments for patients. The approach involves a clonal strategy where stem cells are collected ...

User comments : 0

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.